Bought a Quefrency DIY kit. First time building a keyboard. First time soldering actually, and I'm proud to say I only burned myself 9 times.

I flashed both micro controllers, plugged the keyboard in, and it works. Kinda. About 6 keys don't work. The W key, the S key, the 1 key, and a few others.

I'm looking at the points I soldered and they appear to be good connections.

I've tried and tried to Google, but my Google-fu is failing me deeply today in terms of finding a way to debug this. I definitely should have been more proactive as I built the keyboard and tested parts along the way, but at this stage what would you recommend I do to help diagnose the issue?

Thanks and sorry for the noob question.