Nottingham's NG1 postcode is affected

The Communication Workers Union says it is due to low morale.

The homes and businesses affected are all in the NG1 postal area and are served by the Nottingham City delivery office.

The union says there is no industrial action taking place but some employees are exercising their right not to work overtime.

It says workers are unhappy, partly due to an investigation into a fellow member of staff.

As a result, mail is being delivered late to some properties.

Both the union and Royal Mail say they are trying to resolve the issue.