No special indicator was maintained for coding

What causes this issue?

You must first define the special characters for coding before you can
enter it in the project definition or the WBS element.

System Response

INCLUDE 'NA_ALLG_NOVERARBEITUNG' OBJECT DOKU ID TX

How to fix this error?

INCLUDE 'NA_ALLG_VORGEHEN' OBJECT DOKU ID TX
Enter the length of the identifier for the coding and at least one
special character.

Error message extract from SAP system. Copyright SAP SE.