BT customers are being urged to check their bills for a hidden monthly charge they have unknowingly been paying for months.
An extra £10 has been added to the monthly bills of a number of BT customers, without their knowledge or consent, for several months, according to the BBC.
The charge is for an Xbox Game Pass, that BT customers never signed up for.
Customers have reportedly been complaining about the issue on BT's online help forums since October 2023.
Most impacted customers discovered the error while scanning their bills.
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But others say they received a confirmation email from BT Customer Support, thanking them for activating their subscriptions.
I actually thought I'd been hacked, so I phoned them up... and they explained that it was a BT error.
Sue, an impacted BT customer
All affected customers say they never activated such a subscription - with many not even having an Xbox in their possession.
"I logged into my BT account online and saw that they charged me an extra £10 and that money had come out of my account," one impacted customers named Sue, told the BBC.
"Xbox Game Pass had been added to my accounts without my consent - I thought that's so odd, because I don't even have an Xbox.
"I actually thought I'd been hacked, so I phoned them up... and they explained that it was a BT error."
Refund
Those who have complained to BT have had their money refunded, but they say the experience is concerning.
To contact BT for a refund, simply dial the billing agents' number on the front of your BT invoice.
BT has more information about billing enquiries on its website.
"We're very sorry that the customers mentioned in this article have had Xbox Game Pass Ultimate added to their account without their knowledge," a spokesperson told the BBC.
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"We recommend that all of our customers remain vigilant and if they notice changes to their account that are suspicious, to contact us as soon as possible to report this."
"We will support and guide them on how to take steps to ensure their account is secure."
The spokesperson did not offer a reason for the charge.
However, BT described it as a "known issue" to a BBC employee who was affected by the issue.
BT told another impacted customer, named Craig, that the issue was between BT and Microsoft.
Speaking to the BBC, Craig, contacted the firm via its webchat service, said: "He basically said to me in the chat that this was an issue between BT and Microsoft, where this was being kind of randomly enabled and activated on people's accounts.
"It says in the terms and conditions that there's no free period with this - you are immediately charged.
"My concern is this might not just be me, this might be lots of other people who perhaps don't really notice you get an email through."