& is used as the delivery unit for material & in distribution chain &/&

What causes this issue?

The unit of measure &V1& is still used as the delivery unit in at least
one <DS:GLOS.distribution_chain>distribution chain</> and may not
therefore be deleted.

System Response

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

How to fix this error?

If you want to delete the unit of measure nevertheless, change the
delivery unit to another unit in the distribution chains concerned.

Error message extract from SAP system. Copyright SAP SE.