A temporary mobile testing site was set up in Corby to test key workers for the coronavirus.
But people, who had appointments for the test, were directed to the wrong site after the government sent out the incorrect location.
The testing site is at Corby Town Football Club in Rockingham Road, but people were directed to RS Components in Birchington Road - the opposite side of town.
A spokesperson for NHS Nene CCG said in a statement:
"We apologise for any inconvenience or confusion this has caused. As soon as we were notified of the error we immediately sent personnel to RS Components to redirect residents to the correct site at Corby Town FC. "Those who were booked in on Friday who were not redirected to the correct site can still access a test by attending the Corby Town FC site on Sunday between 10am and 3pm if they bring their booking information with them."
The mobile site in Corby is only open for pre-booked tests only.