Oasis' reunion tour ticket sales were a mess. Now, authorities are zeroing in on Ticketmaster.

• Watch out, Ticketmaster. Today is gonna be the day that they're gonna start a probe on you.
• The UK's Competition and Markets Authority is investigating Ticketmaster's Oasis ticket sales.
• Sales for the highly anticipated Oasis reunion were plagued by sky-high prices.

Don't look back in anger about not getting tickets to Oasis's UK reunion tour.

That's because Ticketmaster, which ran the ticket sales, is now under investigation.

The UK's Competition and Markets Authority (CMA) announced on Thursday that it's investigating whether Ticketmaster wronged the band's fans with its "dynamic pricing" pricing model during ticket sales for Oasis's reunion tour in the UK.

Fans of Oasis — one of the most popular bands at the end of the 20th century — were thrilled when brothers Noel and Liam Gallagher announced they were getting the band back together for the first time in 15 years.

But that excitement quickly soured once fans realized how difficult and expensive it would be to secure tickets to the shows.

Ticketmaster used its "in-demand" pricing model, which increases prices when demand rises. Fans complained of long online queues to buy tickets. When they finally had the chance to buy tickets, fans said prices had surged unexpectedly.

As one fan, Helen Barnett, wrote about her experience on X: "That feeling when you wait in a queue for four hours only to be told the price of the ticket has risen from £148 to... £355??? Because they're 'in demand.' How is this not illegal?"

The UK anti-trust agency said in a press release that it's "scrutinizing whether the sale of Oasis tickets by Ticketmaster may have breached consumer protection law," which mandates that "ticket sales sites must be transparent in their dealings with consumers and give clear and accurate information about the price people have to pay."

Specifically, the CMA is looking into whether Ticketmaster engaged in unfair commercial practices, whether ticket buyers were notified of dynamic pricing and the amount they would actually be paying, and whether buyers were pressured to buy tickets within a short amount of time and at a higher price than they expected.

"It's important that fans are treated fairly when they buy tickets, which is why we've launched this investigation. It's clear that many people felt they had a bad experience and were surprised by the price of their tickets at check-out," Sarah Cardell, the CMA's chief executive, said in the press release, adding that fans should reach out to the agency detailing their Oasis ticket-buying experience.

The CMA noted that its investigation is still in the initial stage, and it should not be assumed that Ticketmaster broke the law.

In a statement to Business Insider, a Ticketmaster spokesperson said, "We are committed to cooperating with the CMA and look forward to sharing more facts about the ticket sale with them."

On its website, the ticket seller explained its policies.

"Promoters and artists set ticket prices. Prices can be either fixed or market-based. Market-based tickets are labeled as 'Platinum' or 'In Demand,'" the website says.

This isn't the first time Ticketmaster has been in hot water over the way it sells tickets.

Last summer, the ticket sale site crashed while millions of Taylor Swift fans were trying to buy tickets for the pop star's upcoming tour. That fiasco prompted the US Department of Justice to file an antitrust lawsuit against Ticketmaster's parent company, Live Nation, alleging the company is engaging in anticompetitive and illegal practices.

After the DOJ announced its lawsuit in May, Ticketmaster said in a statement that the suit wouldn't "solve the issues fans care about relating to ticket prices, service fees, and access to in-demand shows," adding that the company's growth comes from helping artists, fans, and local economies.