I have problems using the internet connection on my Xiaomi 12T Pro

Press Settings.

Press SIM cards & mobile networks.

Press the name of the SIM.

Press Access point names.

Press New APN.

Press Name.

O2 UK Internet

O2 UK Internet

Key in O2 UK Internet and press OK.

Press APN.

mobile.o2.co.uk

mobile.o2.co.uk

Key in mobile.o2.co.uk and press OK.

Press Username.

o2

o2

Key in o2 and press OK.

Press Password.

p

p

Key in p and press OK.

Press MCC.

234

234

Key in 234 and press OK.

Press MNC.

10

10

Key in 10 and press OK.

Press Authentication type.

Press PAP.

Press APN type.

default

default

Key in default and press OK.

Press More.

Press Save.

Press the required data connection to activate it.

Press the Home key to return to the home screen.

Slide two fingers downwards starting from the top of the screen.

Press the mobile data icon to turn the function on or off.

Press the Home key to return to the home screen.

Press Settings.

Press SIM cards & mobile networks.

Press Advanced settings.

Press Data roaming.

Press the drop down list next to 'International roaming'.

Press the required setting to turn the function on or off.

Press the Home key to return to the home screen.

Press and hold On/Off until your phone restarts.