Anushka Banbara said he and all of his workers were forced to get tested for coronavirus immediately when one of his employees came into close contact with a positive case on June 25.

Mr Banbara said his staff member was out for dinner with two others at a Caulfield restaurant for more than an hour.

“The next day my worker was told by one of his dinner guests there had been a positive case at his gym and he needed to be tested for COVID-19. That person and then my staff member tested positive,” he said.

In that time, Mr Banbara’s team had worked together in their Clayton office, but no one else tested positive.

COVIDSafe, which was made available to Australians in April, was developed to help stop the spread of coronavirus.

Once installed, the app uses Bluetooth to check if any other phones with the app installed are within 1.5m of you.

When two phones detect each other they exchange a “digital handshake” meaning each device shares an anonymous ID to log the close contact.

The data is sent to a national store where, if someone reports positive, health officials then phone contacts to tell them they may have been exposed to coronavirus.

But Mr Banbara said he and none of his staff had been contacted by any health authorities.

“We have all been together for longer than 15 minutes and all had the tracking app, but still to this day we have had no communication from the government or the contact tracking team,” he said.

“We work in a tech space so we trust the technology will work but instead we’ve been put at risk by this app, which was promised to work, but clearly doesn’t.”

The Department of Health said all close contacts were identified and notified that they needed to self-isolate and seek testing.

“The Department responds to every case of coronavirus after it is notified to us,” a spokesperson said.

“There are strict procedures in place to protect the public wherever someone tests positive to coronavirus. As part of our contact tracing, relevant public exposure sites are contacted and provided with advice about the transmission risks and any cleaning that may be required.”

Since its launch on April 26, more than 6 million people have downloaded the app.

Victoria has accessed the data of 222 people who were using the COVIDSafe app and had tested positive for coronavirus, according to the Department of Health.

Prime Minister Scott Morrison continued to spruik the benefits of the app on Friday, rejecting a suggestion from a journalist that he had “oversold the benefits” of the technology.

He said the app worked to complement contact tracing done by experts.

“The two work together. They were always intended to work together … That is why I

would continue to encourage people, wherever you happen to be, to download the COVIDSafe app,” he said.

“In most parts of the country there are no community transmission cases, so therefore you wouldn’t expect to be having a high level of use.”

A government official admitted in May that the app doesn’t work properly for iPhone users and its effectiveness “progressively deteriorates” the longer it is not open.

Victoria recorded 288 new infections on Friday, the biggest daily increase anywhere in Australia since the pandemic started.

The state’s total is at 3397, with active COVID-19 cases surging past 1000, Premier Daniel Andrews confirmed.