I have only found three things that worked to "repair" an AnyKey keyboard.

The Ctrl-Alt-SuspendMacro is the first line of defense. If that doesn't work, then disassemble the keyboard (difficult with your model) and clean the Mylar contact sheet, then re-seat and secure (with RTV silicone or with good quality packaging tape) the circuit board where it attaches to the Mylar sheet. The final, last-ditch desperation step (although in your case it will probably have to be the next thing you try) is soaking and "swishing around" the keyboard in warm, soapy water followed by a couple days of drying. That worked for me, but YMMV.

FWIW, both of my "new" replacement keyboards failed last month, in both cases the circuit boards had separated from the Mylar sheet. Some previous owner had repaired this problem before, with two small pieces of Scotch tape. I re-did the repair much more robustly, with full-length strips of clear packaging tape and to my delight, both keyboards subsequently worked perfectly. I'm typing this on one of them now.

If I had to guess, I would say that your current problem with the "N" and the "P" keys is caused by this separation, although there is some doubt because it is only the "N" and "P" keys that have failed. Each one of those circuit traces from the Mylar sheet to the circuit board (there are about a dozen of them IIRC) controls about 10 separate keys, odd that just two of them would fail. It might well be a mechanical problem, dirt on the contacts on the Mylar sheet for those two keys that might be fixed by non-disassembled washing.

About your only other solution would be a good thesaurus where you could look up alternative words without "N"s or "P"s in them...

tanstaafl.