Phil Sands, a medical engineer, who builds and repairs medical equipment at University College Hospital in London, said he had been off work for the last two days after one of his daughters developed a cold over the weekend.

Sands said he had tried more than 50 times to log on to the government’s website to book a test, but each time it either said there are none available or the system crashes.

“It is frustrating that I can’t work, I have no symptoms, there is nothing with me, but following the guidelines I have to stay home until I can prove that I don’t have COVID-19 or the (quarantine) time has passed,” he told Reuters.

Attempts by Reuters reporters to get a COVID-19 test on Tuesday were greeted with a notice on the government’s website saying: “This service is currently very busy. More tests should be available later.”

Chris Hopson, chief executive of NHS Providers, which represents hospital trusts in England, said a growing number of staff were unable to come to work because they or someone they live with had COVID-like symptoms but couldn’t get tested.

He said hospital bosses were working in the dark as they did not know why there were shortages, how long they were likely to last, how geographically widespread they were nor what priority would be given to healthcare workers.

The United Kingdom reported 3,105 confirmed new cases of COVID-19 on Tuesday, up by almost one-fifth from Monday.

“OPERATIONAL CHALLENGES”

Britain advises those showing symptoms to get a test though it says the system has been burdened by people with no symptoms asking for tests. Some schools have demanded any ill students get a test or stay away for 14 days.

Britain’s health minister said the government was working hard to fix what he said were “operational challenges” in the testing system caused by a surge in demand and that it may take weeks to resolve the shortages.

“As we expand capacity further we are working round the clock to ensure everyone who needs a test can get a test,” Matt Hancock told parliament.

Hancock said there had been a sharp rise in people coming forward for tests, including those who were not eligible.

Lawmakers from across the House complained that voters had raised repeated problems with the testing system – including for children whose schools had demanded they have a test if they showed cold symptoms.