Weird A.C. issues- Nest Thermostat

Hello all. I’ve had this issue ever since I’ve purchased my home in 2021. Every year after the winter where I am using my heat; there comes a stupid day like today that is almost 75ish degrees Fahrenheit outside. I live in NC and while it’s been chilly, we’ve had some random warmer days where I would like to simply throw the AC on.

Every single year after using the heat, the AC will no longer come on. When I call for ac, the heat runs. My nest thermostat says it’s cooling but the air out the vents is hot and the temp rises in my home. I have a brand new (in 2020) Goodman combo or package unit on my roof. All electric, no gas. The only thing I’ve ever really had to fix is the capacitor last year. Other than that everything has worked great, besides this issue.

The first time this happened, a company came out and said my thermostat was bad. It was under warranty and when the new one arrived and was installed the AC worked fine.

The next year, same thing happened and instead of paying an hvac company to tell me the same thing, I warrantied my nest through google myself. The new one arrived, I installed and A.C. worked again. That is until I used the heat then tried to go back to AC. I’ve done this every year since owning the home.

Well, here we are again. It’s warm today, I’ve been using my heat already this winter. Go to turn my ac on for a bit and it’s pushing heat. I guess I can easily just tough it out, wait till I no longer need heat, then get it warrantied again for the fourth year in a row.

Being an automotive technician, I know that it’s not the thermostat. Something else is going on here. Idk what. I’ve googled every year and never find an answer. I’m confident in going on my roof to check whatever needs to be checked. I have multimeters, tools, I know how to work with mechanical things. Can someone point me in the direction of what is wrong? I’m sick of warrantying a thermostat that I know is not bad. But something resets every time I change it.