Free Covid-19 tests in England are being scaled back as people scramble for free test packs while they are still available.
In many areas of the country home delivery of free NHS lateral flow tests are unavailable.
People trying to order are discouraged to order packs when they try and access them online.
“Most tests are now needed for people at higher risk,” according to the online ordering system.
“In England, most people without Covid-19 symptoms no longer need to take rapid lateral flow tests.
“Some people still need tests to stay safe, like: NHS staff; people who are at higher risk; people who are visiting high-risk places.
“We want to make sure tests are available for people who need them most.”
There is still confusion within the NHS as to whether tests will still be free for staff.
The NHS Confederation said that workers may be forced to fork out about £50 a month for tests if they have to pay themselves, as it called for clarity over the issue.
The Department of Health and Social Care said that more details would be set out “shortly”.
Free universal testing for the virus will come to an end on April 1, with free tests only being made available to the most vulnerable.
Officials have previously said that the number of free tests available each day will be capped to “manage demand” as the Government scales back free testing for people in England.
The public have been encouraged not to stockpile test packs but since ministers announced the end of the free testing programme for most of the population it has been difficult for many to access them.
But the UK Health Security Agency (UKHSA) said that availability is refreshed regularly.
A UKHSA spokesperson said: “As set out in the Living With Covid plan, from April 1 free tests will only be available for certain groups who are at most risk from the virus.
“In preparation for this change, the gov.uk home ordering channel is asking users to only order test kits if you’re eligible for new Covid-19 treatments, work or volunteer in a high-risk setting or support people who are at higher risk from Covid-19.
“Tests should only be ordered after you have used up any kits you already have at home.”