I had nothing but problems getting the Home app (on multiple devices) to add this device. I also had problems getting the Meross app to add it. I kept getting the ‘unknown error’ message. I have about 20 homekit devices from 3 different manufacturers so I know how to add devices and troubleshoot.
I contacted Meross by their recommended support process (email and then opening a ticket on their site) as well as Twitter, nobody got back to me after 9 days. I gave up and returned it to Amazon, leaving a 1-star review in the process.
Did you get a different brand and, if so, what is your experience with it? I have the MyQ (Chamberlain) and it hasn’t meshed with Alexa or Google Voice the way it advertises. Its door sensor also has terrible battery life. Otherwise good🤷♂️
Fwiw, I have this and had no problem installing or setting up.