Some Keys Not Working

Depends on what switches you have. If the switches let light through to work, then something might be blocking it, If they arent then something else might be wrong. I would suggest taking it apart if you have some tools (screw drivers). Look to see if anything is disconnected, if its not then take the PCB and switches out and then put them back together. That should work but it's not guaranteed; If it doesn't then you should just replace the keyboard. I hope I was helpful!