Volume and mut buttons not working

Hi there, so heres my problem. About a month ago i dropped my phone to the toillette. The only part that got wet was the half bottom of the iPhone. I opened it and put all the parts on rice for a whole night. Everything worked perfectly, i was very happy. This weekend, suddenly the home button wnet dead, i fixed it by changing the flex cable. After fixing it, the volume button just died. Tried everything and theres no way to make them work. What do u recommed for me to do? The power button and the headphone jack work perfectly, thats why its strange to me. So i should just replace the whole flex cable or u recommend to try something before that?

Thanks in advance!