I’ve noticed that since upgrading my WiFi to a net gear mesh, my GC3 loses connection multiple times per day. I see notifications almost every time I look at the panel, even after clearing them each time.
Mesh wifi has a lot of benefits, but it can be problematic for things like cameras and security panels. One possibility is if your router is switching the device from 2.4 to 5ghz repeatedly throughout the day you might be seeing drops.
If you are not able to set a unique SSID for 2.4ghz and connect the panel to it with the new router, it may be good to set up the old router as a dedicated access point just for the security equipment. Use the Mesh router for the rest of your network.