Royal Mail has listed 28 areas in the UK where post might be delayed, with 27 in England and one in Northern Ireland.
Problems with deliveries and late post have concerned residents around the country in fear they may be missing important letters.
A Royal Mail spokesperson said: “All Royal Mail operational sites across the UK, are working hard to deliver the most comprehensive service we can to all our customers in challenging circumstances.
“In common with most organisations, we have a number of employees who are self-isolating in line with official regulations.
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