Is there a local club or group in your area that might be able to help?
Did you buy your equipment from a local store?
Was your quad built by you or someone else?
Is it new or second hand?
If you got it from someone second hand what changes have you made?
You are going to need help to fix this problem, if your gear came from a shop then take it back there and talk to them. If someone else built your quad then you need to get hold of them to fix it or find out if they have a solution or alternative.
If you change the RX you will have to solder, you will also need to be able to solder for any running repairs to the drive system, so ask around family and friends for the loan of a soldering iron, ideally 25-30w, with a stand to hold the iron.