Ac intermittent. 00 fault code

AC started blowing warm air and after some time it's going to blow cold again at intermittent rate. Checked the pressure and it was really low. Recharged it. Then it started doing it again so it's probably losing from somewhere. When I go down to the compressor right after I shut it off I can hear for about 10 seconds some screeching noise. Not exactly like sizzling but somewhat weird. Do you think this is the AC compressor? Cannot locate any obvious leaks at the moment.

Checked the fault AC codes and it says only 00
I would assume it would be showing at least some codes but it doesn't
Any ideas? Thanks