Myki readers on trams and at train stations across Melbourne suffered a system outage on Thursday afternoon, with commuters being waved through the barriers and told not to tap on.
Metro Trains apologised for the inconvenience and said a technical fault was to blame.
Card readers, which Victoria commuters use to tap on when travelling, began displaying “out of order” messages on trains, buses and trams on Thursday afternoon.
However, Metro Trains confirmed on social media about 6pm that the system had been restored, but noted major flooding was causing delays on some lines after heavy rain drenched the city.
Passengers were told to not touch on or off as they passed through the barriers at Southern Cross Station about 5.30pm.
Public Transport Victoria said in a tweet it was aware of the outage and working to restore it as soon as possible.
It thanked passengers for their patience as it worked to resolve the issue.
Metro Trains also took to social media to apologise to commuters.