Bruno Mars concert-goers who were denied entry after buying dud tickets have been told not to delay contacting their bank by the banking ombudsman.
The message comes after a Whangarei woman logged her issue with ticket resale site Viagogo and was told not to contact her bank.
Meanwhile the Commerce Commission is asking people to seriously consider whether Viagogo is really worth the risk.
Letia Hauraki was unable to get into the Bruno Mars' concert at Spark Arena in Auckland.
She had travelled from Whangarei, only to be told at the gate the two tickets she had paid $280 for had been cancelled.
Hauraki logged her issue with Viagogo via a question prompt service on its website, as it cannot be reach by phone.
"Viagogo have responded, sound apologetic but are asking for proof to investigate further that I was denied which I don't have of course so going to Ticketmaster to try and get some sort of proof."
The response she got states the company is "so sorry to hear" she was were denied entry.
"We take situations such as this very seriously and we will commence investigating this issue immediately."
It goes on to request a detailed description of what happened and any documentation that the venue may have provided to confirm the tickets did not permit entry.
The response instructed her not to contact her bank, as it will stop the investigation and initiate a process that could take up to three months, throughout which no refund can be processed.
Hauraki said it sounded like a threat.
Banking ombudsman Nicola Sladden said if the purchase was made using a Visa or Mastercard, her advice would be to immediately let the bank know.
"This allows the bank to promptly look into whether any chargeback process might apply. It is important that affected customers do this within the timeframes set out in the bank's terms and conditions."
The Commerce Commission was investigating Viagogo and advised people to seriously consider whether buying tickets from the site was worth the risk, after the latest series of complaints.
The commission has had 228 complaints about Viagogo to date, including 21 from the weekend, relating not just to Bruno Mars but other recent and upcoming events.
Consumer manager Stuart Wallace said the commission's investigation has been focused on alleged false and misleading representations made by Viagogo which could breach the Fair Trading Act.
"We are currently seeking expert legal advice on whether and how we can enforce New Zealand consumer laws against Viagogo which is based in Switzerland."