If the menu options are greyed out or not working, you can use direct codes to talk to the O2 network servers.
If you’re trying to make a call on your Samsung Galaxy S9 and you hear a message saying “calls are barred” or “call barring is on,” you won’t be able to connect until the feature is turned off. samsung s9 remove call barring o2 uk
This guide is for the Samsung Galaxy S9 running One UI (Android 9/10). O2 UK settings are correct as of 2025. Always check with O2 if you are unsure about your account status. If the menu options are greyed out or
: Tap Supplementary services (on some S9 versions, this may still be listed as More settings ). O2 UK settings are correct as of 2025
Sometimes, users confuse "Call Barring" with other blocking features. Ensure you haven't accidentally enabled (blocking a specific number) or Do Not Disturb mode.