I just bought a unit. It's always failed in QR code. Here's what I have done
Choose locale Mainland
Wifi is unifi 10mbps speed with WPA2 encryption
Choose dafang from the list
Press setup and entered wifi pass and scan QR
At around 60% it successes but then it also said failed
It always failed at around 60-70%

I had power off and on many times also.
I had delete mi home app and clear cache.

I am using iOS.

I am not sure firmware version. From mi home app, I click check for updates and it said no updates available.
So I guess I am on newer possible version firmware.

Guys. Any of you had similar problem ?

Any extra/diff steps that you did compare to mine ?