System error. Asset & not found.

What causes this issue?

The posting transaction tries to replace temporary main asset number &
with a permanent main asset number that is to be stored in the
database. However, the system could not find the temporary asset number
in the global memory of the function group for asset master data
maintenance.

How to fix this error?

Contact your system administrator. There is a program error.

Error message extract from SAP system. Copyright SAP SE.