Hello, I am sorry for the delay. I just logged in and saw your question.
Is the motor you stated on the question that is running is the compressor at the back of the unit?
If it is, then I am afraid that you could had a leak and your unit is now out of refrigerant gas. Or in a rare occasion, the unit would clog up the system and the same symptoms would appear.
Even though, with both scenario, you would need an engineer to do the job because it would require handling of refrigerants which is a controlled substance.
I am sorry if I can not help you with your problem. It is no longer a DIY.
Let me know if you still have any questions regarding your unit.