Internal number assignment not allowed for promotion type &

What causes this issue?

You have not entered a promotion number. However, internal number
assignment is not possible for promotion type &V1&.

System Response

The system cannot create the promotion.

How to fix this error?

Enter the promotion number or assign an internal number range in
Customizing for <DS:SIMG.W_ZF_VK_0220>promotion type</> &V1&.

Error message extract from SAP system. Copyright SAP SE.