APN (or access point name) settings contain information that's needed to make data connections through your phone – especially internet browsing.
In most cases, BT One Phone APN and MMS (picture) settings are automatically set up in your phone, so you can use mobile data straight away.
If you need to update or check your APN settings for BT One Phone, go to your settings menu and find your APN menu. This is often found in the mobile network settings section.
Make sure your APN is set as follows-
|Config option||Configuration information|
You shouldn't need to configure any other information.
If you need to configure your MMS settings, make sure they're set as follows-
|Config option||MMS Configuration information|
Refer to your phone’s user guide for more information.