Im having trouble with my ac again

bought the car 4 months ago, when i got it ac condenser/radiator wasnt working, so i initially thought that was why ac wasnt working. ive had the condenser replaced, and ac worked for a week then it stopped working. Took it back and they said it was a leak in the pipe, it worked again for about a week then stopped working.

so far ive replaced cabin air filter, ac condensor/radiator engine fan assembly and module, engine air filter, had ac refilled, and o-ring for the seal

had a buddy double check and he noticed these issues

compressor is running all the time when ac is on, does not cycle on and off
Low side pressure was high, high side pressure was normal
the lines werent cold/hot

he said the mechanic might not have done a vaccum properly, or it could be something in the compressor is bad
i found out later that the mechanic used the canned freon you can get from stores, , i dont know if it causes issues or not.

checking online, it could be compressor clutch, a leak, or possibly since a vaccum wasnt done on ac, it could have air in the pipes