Variants cannot currently be listed differently if mod. selected manually

What causes this issue?

You manually selected an assortment module.

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?

So as to avoid inconsistencies, you cannot change the variants when in
maintenance.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.