Many O2 customers are facing disruption today (July 12th) after a network fault left tens of thousands of people unable to make calls or access the internet.
The trouble began around lunchtime yesterday and affected users around the country, BBC News reported.
While the operator confirmed this morning its 2G network has been restored, allowing people to make and receive calls, 3G services are still unavailable for some users.
A statement from the firm said: "Our 3G service is starting to restore and customers should expect to see a gradual return of data services as the day progresses."
This is not the first technical problem O2 has experienced this year, as it was forced to apologise in January after a fault caused users' numbers to be disclosed to websites when using data services.
Affected users this time around have been advised to turn off their 3G settings while engineers work on the problem and try switching their phone off and on again.
Posted by Peter Robinson