Disconn. doc. for disconn. reasons 01 and 02 cannot be created manually

What causes this issue?

Disconnection documents with one of the following disconnection reasons
are created by the system automatically:
01 - Disconnection dunning level reached
02 - Vacancy disconnection
You cannot create these types of disconnection documents manually.

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?

Specify a disconnection reason used for manual creation.

Error message extract from SAP system. Copyright SAP SE.