What causes this issue?

You want to select a permit from the proposals in the object structure.
However, no reference object has been assigned to the order. As a
result, there is also no object structure, which could propose the
permits.

System Response

The function cannot be processed.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.