Q: My ac slowly stopped working after just two days.

So my AC has been working in my Mazda for the longest time and every time I take my car to Midas for somthing or an oil change they bring my car back with something else wrong with it which doesn't make any sense and I know sometimes companies do that to get you to come back so the second time I took it to Midas to get a check up when I got my car back that AC slowly stopped working completely within 2 days..could they have drained somthing? My ac works but doesnt blow cold air anymore and the heater works. So my question is is there any way that they could have poked a hole in a hose or drained out the freon or whatever, and how exactly do aCs work, and how can i fix it on my own?

My car's transmission is unknown to me.