The character string & is not a valid XML tag for the IDoc type

What causes this issue?

The character string '&v1&' could not be interpreted as a tag. A tag
was expected '<XYZ>' or '</XYZ>', where XYZ is the
<DS:GLOS.3526B594AFAB52B9E10000009B38F974>IDoc type</>. The tag '<XYZ>'
must follow after the prolog and the optional DTD declaration, and the
IDoc data and tag ' </XYZ>' must be at the end.

System Response

The file cannot be processed.

How to fix this error?

Correct file &v2&.

Error message extract from SAP system. Copyright SAP SE.