Honeywell TH6220WF2006/U Lyric T6Pro WiFi Thermostat

I bought 4 for my 4 zones. I unboxed and installed 1 and it was easy to mount the plate on the wall and wire it, and then the thermostat snapped on and looked good. I got the Honeywell Home app installed on the phone and walked through the configuration (FYI, the phone connects tot he thermostat during configuration via WiFi directly to it.), this and the need for a C-wire if you don't have one is where the professional installation would be needed because the questions are very in depth. Fortunately I installed my own furnace (as well as built the house) so I knew the answers. Then at the end the final step is to configure the WiFi and register it in your account. It had no trouble actually getting the thermostat onto the network, but when the phone switches back to the LAN WiFi it looks for the thermostat to complete the configuration. It timed out and said it was unable to find it and asks to verify i was on 2.4G network. Well, I use the Eero (owned by Amazon) brand mesh network that has both 2.4 and 5G on the same SSID and you have to call tech support to have them turn off the 5G remotely (max 15 minutes). I tried that twice and it would still fail, and each time i had to start all over. Then I found that if I said i was a contractor I could configure everything but the WiFi and the thermostat worked fine, just no remote control, etc. Gave the WiFi only config as home owner a try several more times. Unplugged my Eero network, reinstalled my old NetGear 2.4G only router, which my phone and laptop could use. Ran through the thermostat config several more times trying to use that network, and again always failed with just the 3 devices on the network beside a couple that auto jumped on because I used that same SSID and password hoping that it would just switch over to the Eero netwrok once I got it configured. I literally tried this at least 15 times, many times in various network configurations, finally going so far as to factory reset everything and use the most basic network setup. I am a computer engineer with a minor in networking and couldn't get it to work. What kills me is that when using the Eeros, I could use the Eero App to see the thermostat had joined the network and see it periodically hit the Internet ... which Honeywell tech said was trying to check into the cloud for its registration which is what never got there ... I asked if he could manually add it to my account: "No because of security reasons " ???I'm not sure how adding information to an account is a security issue, vs seeing devices in an account and being able to hit them. Anyway, I spent 2 longs days screwing with this and gave up and carefully removed the one from the wall and repacked it and returned all 4 to Amazon this afternoon. I just got my Eero network back up, and I'm not one to generally review stuff but because I don't think I've ever been so frustrated with something that should be easy, I couldn't wait to bash this crap setup process. I give it 1 star across the board.