Vodafone has apologised after a technical problem led to many users being handed erroneous roaming charges into the thousands of pounds.
Users said on Twitter that in some cases they were told their data had run out, in spite of some of them having data remaining in their monthly allowances.
The bug meant some users outside the UK were left unable to use their phones on Sunday.
Users said they saw their bills rise by hundreds or thousands of pounds within a period of 12 hours, with bills reportedly reaching as high as £5,000.
Some said they were unable to get through to Vodafone to contest the charges or faced a wait time of several hours.
EU regulations that went into effect in 2017 mean UK users are able to make use of their mobile phone minutes, texts and data whilst abroad for no extra charge.
Vodafone said the “technical error” has now been fixed.
It said it is removing the mistaken billing messages automatically, with no need for customers to get in touch for the corrections to take place.
“We are very sorry that some customers could not use their phones yesterday, when roaming abroad. This was due to a technical error, which we have now fixed,” the company said in a statement.
“Some customers are receiving billing messages in error; we are working through these as an urgent priority and are removing any errors from customer accounts.
“Customers will not be charged and do not need to worry about contacting us as we are proactively checking accounts.”
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