Hi reporting this issue because the bottom row on my 3x6 corne's left half doesn't work. I have tried swapping nice!nanos and have narrowed it down to the nice!nano rather than the PCB or solder joints (the other nice!nano from the right side works just fine when reflashing firmware) and the right side now has the exact same issue (bottom row doesn't work).
I've had this corne for a while and the premium case for a decent bit as well. I have no idea what could be causing this for the n!n to be broken as I haven't really opened the keyboard for a while until it broke (yesterday). I haven't been using magnetic charging or anything funky either.