How can I correct a layaway payment (Shift-F4) that was tendered with wrong amount?

If the layaway is still active, you have two options.

Option A:  Recall the layaway, press Shift-F4, and type in a positive or negative amount to offset the current deposit on file.
Example, -50.00 to deduct $50 from current amount on file.

Option B:  Recall the layaway, press Shift-F9, and enter the actual amount of deposit as the deposit over-ride entry.
Example, if deposit on file is $100.00 but value should be $50, change to $50.

In both cases a pop-up message will appear indicating "deposit refund of $xx.xx" will be tendered. You can then tender that amount to the appropriate tender type.