O2 confirmed today that a data outage issue is affecting some customers based in London.
An O2 spokesperson confirmed the outage, stating "we apologise to customers who cannot use data at the moment. We have a fault with the allocation of IP addresses which we are fixing". The O2 network, particularly in London, is notorious for data issues. In July this year network data went offline for an hour for the same reason.
In October, during a BBC interview, O2 Chief Executive Matthew Key confirmed the data issues and stated "We've had some issues, isolated to London. We've now got to the root cause and we think the fix will be coming very soon". Unfortunately it seems the fix hasn't taken place yet as the issues continue to occur for a number of users.