Short version: fixed an earpiece speaker, now the bottom soft keys aren't working. Please help!
The details: I do smartphone phone repairs for friends. I used to work for a phone repair shop so I have a decent amount of experience. Long story short. I was performing a repair on a galaxy s7, the phone had gotten wet and although it is water resistant it's a known issue that the ear speaker tends to become distorted after getting wet. So I opened the back using a hair dryer pretty sparingly and some guitar pics I was very careful not to hit anything, there's a cover underneath the back cover that prevents you from hitting any cables. I unplugged the battery, then the logic board, removed the logic board, removed the speaker, cleaned out some dust and remnants from the water. Replaced the speaker, put everything back together. And when I powered the phone back on the bottom soft keys no longer lit up or worked (the back button and all apps button, the middle button still functions just fine). I retraced my steps being careful to make sure everything was reconnected. I disconnected and reconnected all the cables and the antenna I had touched previously to make sure I didn't make a mistake. Same issue persists. I don't want to order a new screen for them and end up with the same problem, everything else works just fine but those keys now. If you have ever encountered this error or have any possible solutions please assist. Thank you.