Unit of measure & is not assigned to a UoM load category

What causes this issue?

You have entered a document item that contains a material with the unit
of measure &V1&.
For this unit of measure, the system tried to determine a
<DS:DE.METYP>unit-of-measure load category</> for a workload
calculation. However, the system could not find any allocation.

System Response

The system cannot determine a workload because there is no
unit-of-measure load category.
Data cumulation in the information system at the level of the
unit-of-measure load category for the rough workload forecast in the
warehouse or the picking waves in shipping is not possible.
IF &[SWITCH]S4H_DOCU_ON_PREMISE& = 'X'.

How to fix this error?

If the materials with unit of measure &V1& are not included in the
workload calculation, nothing needs to be done.
If these are to be included, however, contact your Customizing
specialist or enter the missing allocation in Customizing for the rough
workload forecast.
ENDIF.

Error message extract from SAP system. Copyright SAP SE.