Validation Error

Hello,



ive got a subform and in it ive put validation IsNull(Front)

validation text : please enter front



and another : IsNull(Back)

Validation text: please enter back





wierd thing is when i enter front i get the error msg please enter front...



and when i press the save button when i dont enter any values im not alerted..



does anybody know whats going on here?

Validation Error