i think the problem is that this was originally created with a different version of Form Builder.
First, delete this line from the page:
<?php require_once("WA_ValidationToolkit/WAVT_ValidatedForm_PHP.php"); ?>
then double click the Server Validation Server Behavior to add any additional validations.
Next, in the server behaviors panel, double click each of the validation show if behaviors, to reset them to the validation that trigger the error.
Add any additional validation show if behaviors you need to show other errors.
For each form element, rebind the initial value to the corresponding validated entries binding.