SAP Message UCF8007 - Place the cursor on a subassignment before executing the function

Diagnosis
The system is attempting to execute the function called up for thesubassignment, which is currently highlighted by the cursor. However,at this moment the cursor is either not touching a characteristic,touching a characteristic that is not a subassignment, or touching akey figure.

System Response
The function cannot be executed.

Procedure
Place the cursor on a subassignment before calling up the function.