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Ticketmaster has landed itself in another royal mess.

The company was hired by the BBC to handle ticketing for a concert on May 7 to celebrate the ascension of King Charles to the British throne. But something went badly awry.

Some fans who received an email from the ticketing site saying they’d won tickets for The Coronation Concert say they were later told that all tickets were gone.

A total of 10,000 free tickets for next week’s concert were allocated to fans in three ballots. Katy Perry, Lionel Richie and Take That will headline the event at Windsor Castle a day after the official coronation ceremony.

But some fans have said Ticketmaster’s instructions on how to secure the tickets allocated in the third ballot were confusing and contradictory.

Fans shared on Twitter screenshots of emails from Ticketmaster saying they had been allocated tickets, but needed to “act quickly” to claim the tickets because they were being offered “to a randomly selected group of ballot winners on a first-come-first-served basis.” But, in some of those screenshots, fans were also told that they had until midday on April 27 to claim their tickets.

“If you do not claim your tickets by this date, then they will be reallocated,” Ticketmaster said in the email, according to a screenshot posted by one Twitter user on Tuesday.

“Like so many others, [I] got the @Ticketmaster email to say I’d got tickets for the Coronation concert but they’re all gone. How can that be?! Atrocious,” the user tweeted.

A Ticketmaster website is shown on a computer screen

Another fan wrote on Twitter Tuesday that she was “beyond disappointed” to lose out on tickets she thought she had won, and criticized Ticketmaster’s “total shambles of a system.”

A spokesperson for Ticketmaster told CNN that any unclaimed tickets from the previous two ballots were released on Tuesday.

These tickets were “released on a first-come, first-served basis to those who had previously applied to the ballot (and were unsuccessful). These inevitably went very quickly,” the spokesperson said.

Only fans who were successful in the first two ballots were offered “guaranteed” tickets, the spokesperson added, provided they claimed their tickets within three weeks.

The BBC, which is organizing the concert, announced in February that the 10,000 tickets would be allocated based on the “geographical spread of the UK population and not on a first-come-first-served basis.”

The broadcaster declined to comment directly on the matter, referring CNN to Ticketmaster’s statement.

Bad blood

The debacle is just the latest in a string of upsets for the ticketing site.

Ticketmaster ran into trouble in November when heavy demand for Taylor Swift’s Eras Tour snarled the platform, infuriating millions of fans who couldn’t snag tickets, including those with a pre-sale code.

Unable to resolve the problem, Ticketmaster canceled a subsequent sale of tickets to Swift’s concerts to the general public, citing “extraordinarily high demands on ticketing systems and insufficient remaining ticket inventory to meet that demand.”

The fiasco has prompted US lawmakers to investigate whether Ticketmaster has a monopoly on selling tickets for events, resulting in higher prices for customers.

Then, in March, some fans said they were unable to access Ticketmaster’s website to secure tickets for the Eurovision Song Contest.

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Jessie Gretener contributed reporting.