Customers of mobile phone giant EE were left unable to make some calls on Tuesday due to a nationwide outage.
EE, which stands for Everything Everywhere, confirmed customers were "reporting problems when trying to make calls".
Dialling other EE numbers didn't seem to be an issue - but users were unable to reach numbers outside the network.
A spokesperson for EE told the Croydon Advertiser: "Some of our customers are reporting problems when trying to make calls to some numbers.
"All data and messaging services are working as normal.
"We’re working to fix this as quickly as possible and apologise for any inconvenience caused."
Some customers were contacting the company to ask when the problem was going to be fixed - and others were less than pleased with the service they'd received and made their feelings known on Twitter.
For those still having issues, customers were advised to get in touch with EE's tech team.
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