seat back won't move; main seat goes forward and back; headrest works. which fuses should I check?

What is your question?

Not much to add; seat back had been working, my wife made an back adjustment, the seatback came forward instead, and that was it. Hasn't worked since.

What makes this problem better or worse?

NA

How long has your 2001 Mercedes-Benz CLK320 had this problem?

a few days