Front office: Reverse step not permitted in step &1

What causes this issue?

You tried to perform a reverse step. However, this is not allowed
according to the process definition.

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?

Check the Customizing settings for the front office.

Error message extract from SAP system. Copyright SAP SE.