Certainly a lot of things can go wrong to impact the A/C system. Considering a Freon recharge was recently required - and no mention of leak repair - the most likely trouble area to check first is the state of freon charge. Fairly easy to check too.
Now, if I were making money on the process, then I'd lay out a long list of things to check and go over them painstakingly one at a time.......
Ken300D