Sleaford’s main post office in Southgate has been temporarily closed.
The surprise news comes after customers arrived at the branch in town on Saturday to find the shutters down without any information notice or staff present.
The post office branch has been run as an agency branch as part of Greenhills Stores for around ten years.
A Post Office spokesman said: “We would like to apologise for any inconvenience caused by the temporary closure of the Sleaford Post Office branch, this is due to operational reasons.
“We would like to reassure customers that we are working hard to restore the service to the community as soon as possible and are committed to maintaining services in the area.
“In the meantime, customers can access Post Office services at any branch, the nearest being Woodside Post Office (part of the Lincoln Road Co-op store).”