When interpreting the results of a lateral flow test, we look for a "C" line to be present which marks a the control area. Where there is a line in this area, the test is valid, when there is not, the test is invalid or inconclusive, and we are unable to issue a result for this test.
This result cannot be altered or the test performed again, and unfortunately this means we are unable to issue a further result.
We know that this can be stressful to hear, as these tests are popular for returning to the UK, and are vital for travel.
We are unable to reissue kits for invalid results and advise you to urgently contact your tour operator or airline to find alternative testing arrangements. It's also worth speaking to your hotel management to ask if they know of a reputable local testing company.