That's concerning. Is the system actually telling you no appointments are available? That looks a possibility from what the web page [www.nhs.uk
] says: "If no tests are available online, do not call the helpline to get a test. No extra tests are available through the helpline." Or is the online system jammed, which also seems a possibility: "This service is currently very busy. If you cannot get a test now, or the location or time are not convenient, try again in a few hours"?