What script did you use?
Validation code for a field only executes if the field is updated. Did you clear the form and enter new data or enter any new data?
The one I used in custom calculation to get the overpayment is event.value = this.getField("Advance").value-this.getField("Total").value; and of course the two fields are reversed to obtain the balance.
And, I appreciate your time to help me.
I have found the following works:
if(event.value <= 0) event.value = "";
Thank you sooo much, it works perfectly!!!