The O2 network is currently down (affecting giffgaff) they are working on fixing the problem. Unfortunately they can't say how long it will take. It's a global software issue caused by Ericsson O2 website states --- The network issue continues to be a top priority for us and we apologise to all our customers impacted by this. Earlier today we suspended any planned works or updates across our systems and network. This allowed hundreds of people from both our technical teams and our third-party supplier’s teams to focus on fixing the problem, helping us to restore data services as quickly as we can which will also help reduce the high network demand we’re currently seeing for voice calls.
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