If you are willing to reprogram it all yet again, you can do a 981 reset and find out whether your eeprom merely has messed up contents (which would be fixed by the 981 reset) or has gotten physically broken.

Do a long press of P, followed by 981. That clears out everything. Next try a 975 learn operation. Next remove a battery and press a key while the battery is out, replace the battery and try another 975 learn. If both 975 learns work, your eeprom contents were messed up and now are fixed. If either 975 learn refuses to try to learn, then the eeprom is probably broken.