The previous owner smashed it whilst attempting to "fix" it.How do you know controller is the problem?
Could you kindly provide a picture?
Thanks for replyingA modern one is for three phase and hall effect motors (brushless motor) , your motor is a simple two phase so is a brushed motor. The two aren't comptible.
One will need a different controller , one for brushed motors.
A brushed speed controller with PAS is very difficult to come by today.