After unlocking Mi6 the activation fails

Jul 25, 2018
The Wi-Fi is connected as is always here (at home) but after tapping "Activate"
with 100% correct password entered MIUI10 says:
"Couldn't verify Mi Account ID. Can't connect to network".
I am not new to computer programming but pretty new to smartphones stuff.
This is the first time I tried to root s phone. Can anybody help please? Thanks!