Hot and cold spots in my house

I’m not sure what is going on with the temperatures in my home, but lately it has been extremely uncomfortable.

Usually I have a nice even temperature at 73 degrees, but even though the thermostat still reads the same temperature, it certainly does not feel like it. I have noticed that there are hot and cold spots all throughout my house, it seems like my house is not heating and cooling evenly. One room will be ice cold and the next room will be overheated. It was incredibly frustrating and I couldn’t handle it anymore. I decided to call a heating and air conditioning business and get their input. They told me they were going to send a certified HVAC tech out, which I was fine with. The HVAC technician was a young kid, but he seemed eager to get work. After he looked at the central HVAC and my house for a while, he came back and told me that my house needed proper insulation. Apparently the insulation inside my walls was really old and falling apart. This was definitely not what I was expecting to hear, and I wasn’t sure how to fix an insulation problem. This entire time I thought it was the A/C device. Thankfully, the A/C worker told me exactly what to do and made the entire process really easy. I worried about the price of getting the insulation fixed, but it actually wasn’t as bad as I was expecting it to be, and I decided to stay at a hotel while the process was taking place.