Personal Form Tab Sequence Stops Working

I have a user who asked for a personal form for tab sequencing on transfer orders.  I created the form for the version he uses of P4210.  The form starts in the From Branch Plant and then goes to the To Branch Plant.  He requested that it tab to the Quantity Ordered in the grid next.

The personal form I developed for him works for the first order he enters.  When he hits the OK (green checkmark) to save the first order, it clears the screen to allow him to enter another order.  The personal form name is still displayed at the top of the screen but the tab sequence no longer works.  It will only work again if he hits the X and clicks add again.