A data entry error is being blamed for some self-quarantining Victorians being wrongly sent a text message telling them their 14-day isolation had ended.
"This was an inadvertent data entry error and we apologise for any confusion," the health department said in a statement on Monday.
"The department is issuing multiple automated messages at different times of the day to thousands of people who may be at different stages of their isolation periods."
Some Victorians in self-isolation due to potential exposure to coronavirus were sent the text message on Sunday morning, days ahead of the end of their quarantine period, the Herald Sun reported.
Those who received the texts included a Melbourne woman who was in self-quarantine with her daughter, who did not get the text message.
Premier Daniel Andrews said he was only aware of about 100 cases where people had been given "more cautious advice".
"From time to time, human errors will be made," he told reporters on Monday.
Mr Andrews said the state's contact tracing team is "bigger than ever before" and included support from the Commonwealth and other states.
"We're having to contact thousands and thousands of people each and every day," he said.
Anyone who is concerned about receiving messages which appear inconsistent are being told to call the coronavirus helpline on 1800 675 398.
Australian Associated Press