Taylor Swift has criticised Ticketmaster after her fans said they waited hours and were repeatedly kicked off the firm's website while trying to get tickets for her upcoming US tour.
The popstar said she and her team had been assured by ticket sellers that they could handle a surge in demand for her Eras tour - her first in five years.
Ticketmaster handled ticket sales for most of the shows on the 20-city, 52-date tour, although SeatGeek sold tickets for a few performances in Texas and Arizona.
In a statement on Instagram, 32-year-old Swift said: "It's really difficult for me to trust an outside entity with these relationships and loyalties, and excruciating for me to just watch mistakes happen with no recourse.
"There are a multitude of reasons why people had such a hard time trying to get tickets and I'm trying to figure out how this situation can be improved moving forward.
"I'm not going to make excuses for anyone because we asked them, multiple times, if they could handle this kind of demand and we were assured they could."
She added: "It's truly amazing that 2.4 million people got tickets but it really p***** me off that a lot of them feel like they went through several bear attacks to get them.
"And to those who didn't get tickets, all I can say is that my hope is to provide more opportunities for us to all get together and sing these songs.
"Thank you for wanting to be there. You have no idea how much that means."
Earlier on Friday, Ticketmaster had cancelled ticket sales for the US tour due to "insufficient ticket inventory" to meet "extraordinarily high demands".
That move came days after the presale for the tour caused the site to crash, leaving many fans frustrated and unable to get tickets.
Fans said they had waited in online queues for up to eight hours, with many finding they were too late for the tickets, which cost between $49 (£41) and $449 (£377) each.
Ticketmaster said on Thursday that it had anticipated heavy demand for tickets, adding that a record 3.5 million people had registered as verified fans.
The company said it had planned to invite 1.5 million of those to participate in the sale for all 52 show dates, including the 47 sold by Ticketmaster, with the other two million placed on a waiting list.
But it said the plan had been undermined by attacks from "bots" - automated software requests - and demand from those who had not previously registered.
Ticketmaster said this had resulting in 3.5 billion system requests - four times the company's previous peak.