Oracle Solution for Error ora-21700

ORA-21700: object does not exist or is marked for delete

What triggered the Error:

er attempted to perform an inappropriate operation to an object that is non-existent or marked for delete. Operations such as pinning, deleting and updating cannot be applied to an object that is non-existent or marked for delete.

What should we do to fix it:

er needs to re-initialize the reference to reference an existent object or the user needs to unmark the object.