Assortment & still has active assignments to assortment users

What causes this issue?

You are attempting to delete an assortment to which assortment users
are still assigned. This is not possible.

System Response

INCLUDE ISR_STOP

How to fix this error?

First delete all the assortment users that are assigned to the
assortment you wish to delete. Then you will be able to delete the
assortment itself.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.