Object name prefix & invalid

What causes this issue?

The prefix &V1& is not a valid namespace.
Repository objects whose names begin with a namespace prefix belong to
this namespace. Namespace prefixes consist of a character string
(letters or digits) enclosed in slashes "/", where the first character
must not be "0".

System Response

The object cannot be edited.

How to fix this error?

Choose a different object name with a valid namespace prefix.

Error message extract from SAP system. Copyright SAP SE.