Formula Suddenly Stopped Working?

I have a 2-lined checkbook register that I have been using for 2 years. The formulas to carry the debit/credit on the top line and then total on the second line are below.

The formulas were working fine and then suddenly I now get a #value! error on both lines and all lines below. I checked the formatting and the cells are formatted as they should be for negative/positive numbers. Can someone tell me what is wrong with these formulas?


=IF(D7655>0,0-D7655,IF(D7655+E7655=0,"",E7655))

=IF(AND(ISBLANK(D7655),ISBLANK(E7655)),"",SUM(F7654-D7655+E7655))

THANKS for your help!

I found out why! There was a damn space in the debit column and the formula is, of course, expecting a number or blank. So as soon as I removed the space, everything worked again.

Thanks Dave for trying to help...