Thanks for the pictures.
That coil wire length looks fine, not too short or long.
I wear N7 and K2 processors. Typically about 6 months each for cool and warm weather reasons.
I have not had any issues with the coils. I do not put them in a dryer each night, only in really wet circumstances will I use the dryer, like stepping into the shower once.
Making sure the connection is tight on the processor is about the only thing I can think of. The phone app has nothing to do with the processor working. It is just for changing setting, streaming and looking at status.