Thousands of people waited in the queue for tickets, with many posting screenshots of messages telling them they were 11,879th in the queue.
Presale for Lizzo’s January 2020 Truth Hurts tour event began on Wednesday 20 November. There are fewer than 6,000 seats at the Sydey Opera House.
At the time of writing, Viagogo had a single floor ticket listed for as much as $19,000 (£10,000) on its site.
A statement from the Sydney Opera House to The Guardian said it was monitoring fraudulent behaviour and would not be sending tickets out until the day of the event.
“The Sydney Opera House takes ticket scalping very seriously,” it said. “Across all Sydney Opera House events we have system checks in place to monitor fraudulent behaviours, and tickets may be cancelled without notice if these checks detect any anomalies.
“As is standard practice, tickets for Lizzo’s Sydney Opera House show will only be dispatched on the day of the event – Monday 6 January, 2020 – to restrict unauthorised resales.”