Part of the rear parking sensor is pushed in and causing false beeps whenever I'm on reverse.
Is the sensor totally pushed in and hanging by the wires or pushed in a little? Either way you have to determine which parts are damaged: the sensor itself, the bezel for it or the bumper. The sensor and bezel snap into place, so if they are damaged they will need to be changed. The bumper cover will need to be removed for repair. Neither of the the parts come painted unless bought used. Read the car’s manual to see if there is a button to disable the parking aid. If you need help, a qualified mechanic from YourMechanic can come out and inspect the beeping noise.