Ticketmaster has apologised and refunded a customer who was sold tickets to a gig in Belfast that already been sold to another couple.
Carla Cochrane had bought tickets for her and partner Thomas to the "Biggest 80s and 90s Disco" event at the SSE Arena on Saturday night.
She had also booked a hotel for the night with the couple travelling from Lurgan.
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"We scanned our tickets at the door, everything straightforward and went to the bar and got a drink," she said.
"We then moved on and when we got round to the seats, there were people on them.
"Sometimes people do move up a seat or two when they think there's people not coming so I said 'sorry I think you're in our seats'.
"But the man sitting there showed me his phone with their tickets and it was identical to mine.
"Obviously they were in their right seats too so they weren't going to give those up either, which is fair enough.
"We just sort of said to each other, there's not much we can do here, we're going to have to go."
Carla had paid £110 for the tickets and said she had spent a further £190 on the hotel for the night.
When she emailed Ticketmaster initially to complain about the mistake, she was told they no longer held her money and she would have to contact the promoter instead.
Another customer service representative then told Carla that Ticketmaster's general policy was not to offer refunds or exchanges, but that on the rare occasions they did, those needed to be processed before the relevant event.
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After Belfast Live contacted the ticket selling giant highlighting the issue, Ticketmaster acknowledged that a "mistake has been made here".
The company said it apologised "for any inconvenience caused" and that a refund to Carla should appear in her account within a few working days.
Carla said she had spoken out to highlight the mistake for fear that it might happen to another person or that it could happen again in the future.
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