Reason & for movement type & not defined

What causes this issue?

When posting inventory differences, you chose a reason that is not
defined for this movement type.

System Response

The system only accepts reasons that have already been defined for
movement types.
IF &[SWITCH]S4H_DOCU_ON_PREMISE& = 'X'.

How to fix this error?

If you have authorization to do so, in Customizing for Inventory
Management you can define your own reasons for movement types.
ENDIF.

Error message extract from SAP system. Copyright SAP SE.