Hello,
Got that problem but with 4G connection at the time trying activation Mi Message, and solved with this method:
NOTICE!: All your saved connections will be lost!
1- Go to or tap on
Settings.
2- Then Tap on
Connection & Sharing.
3- Then go all the way down to tap on
Reset WLAN, mobile networks, and Bluetooth.
4- Then confirm Tapping on
Reset settings below.
For now I've restored my 4G mobile connection, will not activate Mi Message and see how long it will last.
Good Luck.
EDIT!:
Another Solution, which involve data package, so follow the instruction attached below, Man this phone drives me wild but I keep Loving it