All air conditioning

I had them I stall a new air conditioning until at the beg5of 2020. The 1st year it was fine, no problems, after that they have been out every year and sometimes more than once. This past August the motor went out (again) it was alot of run around, but it got done to the tune of $549 (mind you the part was under warranty. Yesterday i go to turn on my heat and nothing happened. I tried call All Air and Heat, I left a message, no call back and when I tried again, I got a recording that the number I was calling was not accepting calls at this time. I ended up calling another company to come out. I found out that All Air and Heat did not change both wires from the thermostats to the units. They only changed 1 and left an old wire. They were not grounded properly and that why I kept having so