Welcome. My name is XXXXX XXXXX would be glad to assist.
When measurements indicate voltage on the neutral, that represents a loose connection in the circuit.
All connection/tap points need to be checked and possibly remade.
Power flows out on the Hot wire and then returns on the neutral back to the utility transformer.
A simple loose connection will drive the neutral up from 0 volts because the current is unable to fully return.
This happens quite often, especially when there are receptacles on the circuit and they are wired with the push in back connections.
The side screws will eliminate most of these issues on receptacles and switches
Light taps with the neutrals, must have a good copper to copper connection with no corrosion also.
If you have several weak point connections, they will add up to a largher issue when together and cause this problem.
Hope that gives the details, just reply for any additional.