If Freon is placed in a freon system for 4months is the entire unit now ruined or can it be repaired?

answer to first question if someone put R22 freon in a unit that should have had puron it it,, I`m surprised it lasted 4 months,, it is probably gummed up so bad, compressor locked up,, that all you can do is replace the entire system,, meaning=condenser--evaporater--and lineset

maybe someone else can come up with a wonder-drug that might help I don`t no about