Remote Computer File Transfer PowerShell script does not do logging correctly

This is my remote computer file transfer PowerShell script:

#--------------------------------------------------------[Initialisations]-------------------------------------------------------

#Clears the contents of the DNS client cache
Clear-DnsClientCache

#Loading script configuration
$configuration = Get-Content '.\Resources\Remote Computer File Transfer Configuration.cfg' | Select-Object | ConvertFrom-StringData

#Initializing report file
New-Item -Path $configuration.ReportFile -ItemType File

$fileList = Get-Content -Path $configuration.FileList
$computerList = Get-Content -Path $configuration.ComputerList

#Initializing file counters
$successfulTransfers = 0
$failedTransfers = 0

#---------------------------------------------------------[Functions]----------------------------------------------------------

function Write-Log
{
    param
    (
        [Parameter(Position = 0, Mandatory = $false)]
        [String]
        $OperationSuccessful,

        [Parameter(Position = 1, Mandatory = $false)]
        [String]
        $Message,

        [Parameter(Position = 2, Mandatory = $false)]
        [String]
        $LogSeparator
    )
    if($null -eq $LogSeparator)
    {
        $timestamp = Get-Date -Format "yyyy.MM.dd. HH:mm:ss:fff"
        $logEntry = $timestamp + " - " + $Message
    }
    else
    {
            $logEntry = $LogSeparator
    }

    
    if($OperationSuccessful -eq "Successful")
    {
            Write-Host $logEntry -ForegroundColor Green -BackgroundColor Black
    }
    elseif($OperationSuccessful -eq "Failed")
    {
            Write-Host $logEntry -ForegroundColor Red -BackgroundColor Black
    }
    elseif($OperationSuccessful -eq "Partial")
    {
            Write-Host $logEntry -ForegroundColor Blue -BackgroundColor Black
    }
    else
    {
        Write-Host $logEntry -ForegroundColor Yellow -BackgroundColor Black
    }
    
        Add-content -Path $configuration.LogFile -Value $logEntry
    
        Add-content -Path $configuration.ReportFile -Value $logEntry
}

function Send-Report
{
    param
    (
        [Parameter(Position = 0, Mandatory = $true)]
        [string]
        $FinalMessage
    )

    if($configuration.SendReport -eq "true")
    {
        $body = $configuration.Body + "`n" + $FinalMessage

        Send-MailMessage -SmtpServer $configuration.SmtpServer `
                         -Port $configuration.Port `
                         -To $configuration.To `
                         -From $configuration.From `
                         -Subject $configuration.Subject `
                         -Body $body `
                         -Attachments $configuration.ReportFile
                         
        Remove-Item -Path $configuration.ReportFile
    }
}

#---------------------------------------------------------[Execution]----------------------------------------------------------

Write-Log -LogSeparator $configuration.LogTitle
Write-Log -LogSeparator $configuration.LogSeparator

#Get credential from user input
$credential = Get-Credential

$message = "User " + $credential.UserName + " entered credentials"
Write-Log -Message $message

foreach($file in $fileList)
{
    if((Test-Path -Path $file) -eq $true)
    {
        $message = "Successfully checked " + $file + " file - ready for transfer."
        Write-Log -OperationSuccessful "Successful" -Message $message
    }
    else
    {
        $message = "Failed to access " + $file + " file. It does not exist."
        Write-Log -OperationSuccessful "Failed" -Message $message
        $message = "Script stopped - MISSING FILE ERROR"
        Write-Log -OperationSuccessful "Failed" -Message $message
        Write-Log -Message $configuration.LogSeparator
        Send-Report -FinalMessage $message
        Exit
    }
}
$message = "Successfully accessed all files - ready for transfer"
Write-Log -OperationSuccessful "Successful" -Message $message

#Start file transfer
Write-Log -Message "Started file transfer"
foreach($computer in $computerList)
{
    #Mapping network drive
    if((Test-Connection -TargetName $computer -Quiet -Count 1) -eq $true)
    {
        $message = "Successfully accessed " + $computer + " remote computer"
        Write-Log -OperationSuccessful "Successful"-Message $message

        #Network path creation to D partition on the remote computer
        $partition = "\D$"
        $networkPath = "\\" + $computer + $partition

        #Try to create network drive to D partition on the remote computer
        if(New-PSDrive -Name "T" -PSProvider "FileSystem" -Root $networkPath -Credential $credential)
        {
            $message = "Successfully mapped network drive to D partition on the " + $computer + " remote computer"
            Write-Log -OperationSuccessful "Successful" -Message $message
            $driveMappingSuccessful = $true
        }
        else
        {
            $message = "Failed to map network drive to D partition on the " + $computer + " remote computer"
            Write-Log -OperationSuccessful "Failed" -Message $message

            #Network path creation to C partition on the remote computer
            $partition = "\C$"
            $networkPath = "\\" + $computer + $partition
            
            #Try to create network drive to C partition on the remote computer
            if(New-PSDrive -Name "T" -PSProvider "FileSystem" -Root $networkPath -Credential $credential)
            {
                $message = "Successfully mapped network drive to C partition on the " + $computer + " remote computer"
                Write-Log -OperationSuccessful "Successful" -Message $message
                $driveMappingSuccessful = $true
            }
            else
            {
                $message = "Failed to map network drive to C partition on the " + $computer + " remote computer - Credential not valid"
                Write-Log -OperationSuccessful "Failed" -Message $message
                $driveMappingSuccessful = $false
            }
        }
    }
    else
    {
        $message = "Failed to access " + $computer + " remote computer - OFFLINE"
        Write-Log -OperationSuccessful "Failed" -Message $message
        $driveMappingSuccessful = $false
    }

    if($driveMappingSuccessful)
    {
        $path = "T:\" + $configuration.TransferFolder

        if((Test-Path $path) -eq $true)
        {
            $message = "Successfully accessed " + $path + " folder"
            Write-Log -OperationSuccessful "Successful" -Message $message
            $deployingFolderSuccessful = $true
        }
        else
        {
            $message = "Failed to access " + $path + " folder - MISSING FOLDER ERROR"
            Write-Log -OperationSuccessful "Failed" -Message $message

            try
            {
                New-Item -Path $path -ItemType "Directory"
            }
            catch
            {
                Write-Log -OperationSuccessful "Failed" -LogSeparator $_.Exception
            }

            if((Test-Path $path) -eq $true)
            {
                $message = "Successfully created " + $path + " folder"
                Write-Log -OperationSuccessful "Successful" -Message $message
                $deployingFolderSuccessful = $true
            }
            else
            {
                $message = "Failed to create " + $path + " folder"
                Write-Log -OperationSuccessful "Failed" -Message $message
                $deployingFolderSuccessful = $false
            }
        }

        if($deployingFolderSuccessful)
        {
            $fileList = Get-Content -Path $configuration.FileList

            foreach($file in $fileList)
            {
                #File name extraction from file full path
                $fileName = Split-Path $file -leaf
        
                try
                {
                    Copy-Item -Path $file -Destination $path -Force
                }
                catch
                {
                    Write-Log -OperationSuccessful "Failed" -LogSeparator $_.Exception
                }

                $transferDestination = Join-Path -Path $path -ChildPath $file

                if(Test-Path -Path $transferDestination)
                {
                    $message = "Successfully transferred " + $fileName + " file to " + $transferDestination + " folder"
                    Write-Log -OperationSuccessful "Successful" -Message $message
                    $successfulTransfers ++
                }
                else
                {
                    $message = "Failed to transfer " + $fileName + " file to " + $path + " folder"
                    Write-Log -OperationSuccessful "Failed" -Message $message
                    $failedTransfers ++
                }
            }
        }
        else
        {
            $message = "Canceld file transfer to " + $computer + " remote computer"
            Write-Log -OperationSuccessful "Failed" -Message $message
        }
    }
    else
    {
        $message = "Canceld file transfer to " + $computer + " remote computer"
        Write-Log -OperationSuccessful "Failed" -Message $message
    }

    #Network drive removal
    if($driveMappingSuccessful)
    {
        Remove-PSDrive -Name "T"
    }
}

$message = "Completed Remote Computer File Transfer PowerShell Script"
Write-Log -Message $message

if($successfulTransfers -gt 0)
{
    $message = "Successfully transferred " + $successfulTransfers + " files to " + $Destination + " folder"
    Write-Log -OperationSuccessful "Successful" -Message $message
}

if($failedTransfers -gt 0)
{
    $message = "Failed to transfer " + $failedTransfers + " files to " + $Destination + " folder"
    Write-Log -OperationSuccessful "Failed" -Message $message
}

if(($successfulTransfers -gt 0 ) -and ($failedTransfers -eq 0))
{
    $message = "Successfully transferred all files to " + $Destination + " folder"
    Write-Log -OperationSuccessful "Successful" -Message $message
}
elseif(($successfulTransfers -gt 0 ) -and ($failedTransfers -gt 0))
{
    $message = "Successfully transferred some files to " + $Destination + " folder with some failed"
    Write-Log -OperationSuccessful "Partial" -Message $message
}
elseif(($successfulTransfers -eq 0 ) -and ($failedTransfers -gt 0))
{
    $message = "Failed to transfer any file to " + $Destination + " folder"
    Write-Log -OperationSuccessful "Failed" -Message $message
}

Write-Log -Message $configuration.LogSeparator

#Sends email with detailed report and deletes temporary report log file
Send-Report -FinalMessage $message

This is .cfg file:

LogTitle = ***********************************************  Remote Computer File Transfer PowerShell Script Log  ************************************************
LogSeparator = ******************************************************************************************************************************************************

SendReport = true

LogFile = .\\Resources\\Remote Computer File Transfer Log.log
ReportFile = .\\Resources\\Report.log
FileList = .\\Resources\\File-Paths.txt
ComputerList = .\\Resources\\Computer-List.txt
TransferFolder = _INSTALL

SmtpServer = smtp.mail.com
Port = 25
To = [email protected]
From = [email protected]
Subject = Remote Computer File Transfer Report
Body = This is an automated message sent from PowerShell script. Remote Computer File Transfer PowerShell Script has finished executing.

Something is wrong with logging. It must be a problem with Write-Log function. The script actually does the job but nothing is written on the console by Write-Log function, and it just writes this in the picture and I can't figure out why.

Grateful in advance!