Melbourne mother Sarah had been looking forward to taking her daughters, aged 10 and 13, to the Friday concert, but discovered she had inadvertently acquired stolen tickets, she told AAP.
The person who originally owned the tickets had their account hacked, and the tickets sold to a third party who on-sold them, Sarah said.
An hour spent at the Ticketek's Melbourne Cricket Ground booth on Thursday failed to resolve the issue, and Sarah said staff were "clearly bamboozled" by the case.
"Their own system has let them down, maybe they should tell my 10 year old and deal with the tears," she said.
Sarah says the transactions took place on Ticketek's resale platform, but the company disputes this.
"This customer did not purchase her tickets through any official Ticketek platforms ... therefore we are unable to verify whether the customer's tickets are valid," a spokesperson told AAP.
Another Swift fan Sophie Le, 33, had four concert tickets but said she discovered on Thursday that her account had been hacked and her tickets sold.
"I'm just holding on to hope at the moment, I was distraught," she said.
The audience across the three nights in Melbourne is expected to be about 260,000 fans, and Ticketek said it was working around the clock to help people with ticket issues.
"Ticketek is aware of unauthorised access to individual accounts via information that has been obtained from other sources," a company spokesperson said in a statement.
"Unfortunately, our team are also dealing with thousands of queries that either relate to fraudulent tickets or other scams," the spokesperson said.
If customers suspect tickets have been resold fraudulently, they should contact police, and Ticketek would investigate, the company said.
Ticketek has also shut down scam sites claiming to be the Marketplace resale platform, and was monitoring the internet and social media to remove scams, the company stated.
Sarah can't see how her ticket issues can be resolved ahead of the concert, and said she was angry Ticketek couldn't verify whether her purchase was legitimate.
"They seriously need to invest some money in cybersecurity or stopping fraud or something ... and in the meantime there's no tickets," she said.
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