O2 customers across the country found themselves unable to make or receive phone calls on Wednesday afternoon after the UK network suffered a national outage.
"We are currently seeing a problem on our network affecting some of our customers. Those customers affected will have difficulty making or receiving calls, sending texts or using data," said the carrier via its service status page and then through Twitter. "Our engineers are dealing with the problem as a priority and we hope to restore full service as soon as possible."
However, that hasn't stopped customers airing their annoyance on the social network, with many claiming they will move away to another operator because of the fiasco.
"If you've tried to call me, apologies - the @02 #O2 network is down, and has been for SEVERAL HOURS - almost unimaginable incompetence," said Mike Southon on Twitter, voicing what many people thought on the social network.
Twitter user Chris Fountain turned to the social network to say: "So it turns out o2 has gone down and I'm one of the unlucky ones!! cheers o2 #inconvenient"
Lisa Miguez, another disgruntled Twitter user felt it was akin to going back to a time before mobile phones: "Seems my O2 voice and text is down. All radio silence here tonight. Back to pen and paper."
But it's not just O2 customers that are feeling the silence, O2 also provides network coverage for Tesco Mobile and Giff Gaff customers.
O2 is working on fixing the problem, but at this point in time, there is no fix in sight.
There could be several reasons as to why the network has failed. However, as it is a national problem rather than a localised one, it is likely to be something that is affecting the whole network rather than just a fault at a single exchange, because of flooding or theft.
UPDATE WEDNESDAY 11 JULY 21:49 GMT: O2 has updated the status of the problem, but it's not good news.
On Twitter around 21:30 GMT the company said: "Our engineers are continuing their work to fully restore service to customers with network issues as a priority. http://status.o2.co.uk"
The status page has no further information other than the statement O2 posted at 13:30 on Wednesday.
UPDATE WEDNESDAY 11 JULY 23:18 GMT: A spokesperson for O2 has told the BBC the following:
"The problem is an issue within part of our core network that is preventing some mobile phones from successfully connecting. The problem is not location-specific."
UPDATE THURSDAY 12 JULY 00:03 GMT: O2 has confirmed that it is still working on the problem with a statement on the status page:
"Our engineers and vendors are continuing to deal with the problem as a priority and we hope to restore full service as soon as possible."
UPDATE THURSDAY 12 JULY 07:00 GMT: O2 has made further statements on its status update page through the night. The company has confirmed that it knows what the problem is. Sadly for O2 customers is doesn't yet know how to fix that problem.
"05:40 - We're continuing to drive the recovery of this issue with our support teams and vendors. We're working to restore service as quickly as possible. Unfortunately we're unable to confirm any timescales for service restoration at this time. We'll let you know as soon as we can. We apologise once again for any inconvenience this incident is causing.
"03:25 - We're still working with our support teams and vendors trying to restore service as quickly as possible. We apologise for any inconvenience caused whiile this recovery work is in progress. We'll provide further updates as soon as we can.
"01:00 - We can confirm that the problem with our mobile service is due to a fault with one of our network systems, which has meant some mobile phone numbers are not registering correctly on our network. As a result, some customers are having difficulty making or receiving calls, sending texts or using data. We, and our central supplier, have deployed all possible resources and are working through the night to restore service as soon as possible. We apologise again to customers affected and will provide further updates as soon as we can."
UPDATE THURSDAY 12 JULY 10:00 GMT: Good news finally as O2 has restored its 2G service, though 3G is seemingly taking a little longer:
"We can confirm that our 2G network service has now been restored. Customers who were affected should now be able to make and receive calls. Our 3G service is starting to restore and customers should expect to see a gradual return of data services as the day progresses.
Customers affected may wish to try switching their mobile phones off and on as service returns.
We are sorry again for the inconvenience this has caused some customers and can provide reassurance that we continue to deploy all possible resources, and will do so until full service is restored."
We will keep you posted.