From where to execute business logic after adding data to database? (MVC)

I have a simple CRUD application in MVC using EntityFramework. I need to use an external API after creating a new element, but I am not sure from where to do that.

I have read in multiple threads on this website and others that business logic should be in the Model and not in the Controller, however I am not sure how to get it to work.

This is what my Model looks like:

public int ID { get; set; }

private string _name;
[Required(ErrorMessage = "Required")]
public string Name
{
    get { return _name; }
    set
    {
        _name= value;
        if (value != null)
        {
            this.doAPIStuff();
        }
    }
}
[Required(ErrorMessage = "Required")]
public string PersonalNumber { get; set; }

public void doAPIStuff()
{
    // do stuff
}

As you can see I am trying to execute my doAPIStuff() method after adding data to the database, however when I do input something in the field Name I get an error The value '<value>' is invalid (where is what I have written in the text box).

Neither of these helped me solve my problem:

The value “(string)” is invalid

ASP.NET MVC Page Validation Fails (The value is invalid.)

DropDownList Value is always invalid in MVC 3

I have not touched the View - here is most of it:

@using (Html.BeginForm()) 
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>Person</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Name, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Name, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Name, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.PersonalNumber, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.PersonalNumber, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.PersonalNumber, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </div>
    </div>
}

I did test the code from doAPIStuff() in my Controller, so I know for sure that it works, however I am not sure how to run it as shown above. Another option I was thinking of was creating a new model just for the doAPIStuff() method, however then I would have to pass the Name and PersonalNumber values to the Model, which seems like the wrong thing to do.