Why git asks for username when ran inside a script?

I have a Push command, that runs this script:

FindGits |
{
    while read gitFolder; do
        parent=$(dirname $gitFolder);
        if [[ `git -C $parent status --porcelain` ]]; then
            echo;
            (
                echo $parent;
                git -C $parent status --porcelain
                git -C $parent add .
                git -C $parent commit -m "committed by script" 1>/dev/null 2>/dev/null
                if [[ $? == 128 ]]; then
                    git -C $parent commit -m "commited by script" 1>/dev/null 2>/dev/null
                    git -C $parent push
                    if [[ $? == 1 ]]; then
                        git -C $parent pull
                        git -C $parent push
                    fi
                else 
                    git -C $parent push
                    if [[ $? == 1 ]]; then
                        git -C $parent pull
                        git -C $parent push
                    fi
                fi
            ) &
        fi
    done
    wait
}

However, when I run it, git asks for username:

Username for 'https://github.com':

Here are the tests I have done, to make sure git has access to GitHub:

• ssh -T [email protected] => successful
• sudo -i + ssh -T [email protected] => successful
• I go into a git repository, and I change something, and I manaully add + commit + push => successful
• I go to my home, and add + commit + push from another repository using -C another_git_repo_path => successfull

Then why it does not work when I run it from inside a script?