jQuery-submit forms after preventDefault

There is such a code, I check the existence of the entered value in the database via ajax: 

$(".cu_process").on('submit', function(e) {
    
    e.preventDefault();
    $.post('/checkurl?type=' + $(this).attr('type'), { url: $(".url").val() }, function(data) {
        
        if (data == "true") alert("Ссылка уже существует");
        else {
            $(this).unbind('submit').submit();
        }

    });
});

If everything is fine, else is executed, but the line $(this).unbind('submit').submit(); does not work, is there any way to continue sending the form?

Author: Daniel Protopopov, 2020-09-17
Source