while loop with operator++ only counting up once

I adopted code from https://stackoverflow.com/a/44553006/8719001

but can't figure out why when uploading the same file "test.jpg" several times it only counts up once, creating "test-1.jpg" but not more ie. test-2.jpg, test-3.jpg.

Can anybody spot the issue and help please?

 $keepFilesSeperator = "-";
 $keepFilesNumberStart = 1;

if (isset($_FILES['upload'])) {
        // Be careful about all the data that it's sent!!!
        // Check that the user is authenticated, that the file isn't too big,
        // that it matches the kind of allowed resources...
        $name = $_FILES['upload']['name'];
        //If overwriteFiles is true, files will be overwritten automatically.
        if(!$overwriteFiles)
        {
    $ext = ".".pathinfo($name, PATHINFO_EXTENSION);
            // Check if file exists, if it does loop through numbers until it doesn't.
            // reassign name at the end, if it does exist.
    if(file_exists($basePath.$name))
            {
                    $operator = $keepFilesNumberStart;

                //loop until file does not exist, every loop changes the operator to a different value.
            while(file_exists($basePath.$name.$keepFilesSeperator.$operator))
                {
                        $operator++;
               }
               $name = rtrim($name, $ext).$keepFilesSeperator.$operator.$ext;
            }
        }
        move_uploaded_file($_FILES["upload"]["tmp_name"], $basePath . $name);
    }

your while loop condition has a problem

while( file_exists( $basePath.$name.$keepFilesSeperator.$operator ) )

the $name variable still contains the full name of file, in this case test.jpg, you're testing a value like /home/test.jpg-1 so finally the while loop is never executed as the file test.jpg-1 never exists, that's why you always get the test-1.jpg on disk and not a ...-2.jpg or ...-3.jpg