Many ticketholders for cancelled Olly Murs concerts in Dorset and Devon will not be refunded after the promoter went bust.
The singer was to perform at Exeter's Powderham Castle on 29 July and at Kings Park, Bournemouth on 5 August.
Stephen C Associates Limited, which organised the events, said it had ceased trading.
In a statement the promoter said: "The company is not in a position to offer you a refund."
Only those who bought tickets from Stephen C Associates Limited using their credit cards can claim their money back, it said.
"If you are not protected in this way because you bought your tickets by some other means, it would appear that you will not be able to recover your money," the promoter added.
Many, including Lynsey Welstead from Bournemouth, paid for their tickets using debit cards.
She spent £130 for three tickets as a Christmas present for her sons.
"My boys are such big fans of Olly Murs. It would have been their first concert - it's really disappointing," she said.
BH Live, a ticket agent for the Bournemouth concert, said it would contact those who bought tickets through it "shortly to arrange a full refund".
Olly Murs tweeted: "I'm so gutted for my fans in Exeter and Bournemouth. Although it's out of my control I'm still so sorry and hope I can get to see you all soon!"
Lorna Wilson, who bought four tickets for her daughter's birthday, said: "His apology is not good enough. He should step up to the mark and sort this mess out."
The BBC has contacted Olly Murs' management for a comment.
Powderham Castle, home to the Earl and Countess of Devon, was also due to host a concert by Bournemouth Symphony Orchestra on 30 July organised by the promoter.
In a statement Charlie and AJ Courtenay said: "While we cannot hope to make up for the disappointment of missing these shows, we are looking at ways to make a gesture for those who have bought tickets."
Bournemouth Symphony Orchestra said it was "very disappointed" at the cancellation and said any tickets which had been bought directly from the orchestra would be fully refunded.