EE customers are being urged to check their bills after users reported being charged thousands of pounds in a data roaming glitch.
Travelling customers have been hit with extra charges despite paying for data roaming add-ons.
Mobile phone users are already used to roaming charges when travelling abroad, especially outside of Europe.
Many pay for add-ons to avoid excessive fees.
For example, EE customers can buy a travel pass that gives them 500MB of data for £5.02 per day in Canada and the USA or £6.27 in Australia.
But a data roaming glitch has meant some customers are being charged thousands of pounds abroad despite staying within the limit.
In some cases, users are being told to settle the bill or their phone contract will be suspended.
One Twitter user said his son had purchased a data roaming add-on to travel in California but was told he owes £2,000.
Another Twitter user said: “I purchased roaming add-on for USA I’ve been charged nearly £300 for about 40MB of data.
“An EE representative said this is a known issue.”
A traveller working in the USA said on Twitter that he had more than £1,000 of roaming data added to his bill and his account suspended
A different person told The Daily Telegraph that they had been incorrectly charged £25,000 after a month in the US.
EE apologised to customers and said the glitch had been resolved in a statement to the paper, which said: “We are contacting affected customers to reassure them that they won’t have to pay for these incorrect charges.”
The Sun has asked EE for further comment.
It comes as EE, like other mobile providers, has brought back data roaming customers for British customers travelling in Europe.
See all the networks that are bringing data roaming charges back on the continent.
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