I got a call from this number today saying they're from test and trace. Guy knew my name and isolating dates. He asked how I was doing. He read a script. I asked him if I can go work on the day or day after. He was eager to get off the phone. He also yawned during the call which wasn't professional. I rang 119 who said this looks like a cold calling number and not the NHS number which would be +443000135000
Called stating NHS Track and Trace and needed information as close contact with positive case. I said tried doing online system but as out of country address could not do. Asked me if I had any address in U.K., when said no not lived there for 4 years they hung up!