Network profile does not exist. Change project definition

What causes this issue?

You have not entered a network profile in the project definition.
The system requires a network profile in order to schedule dates.

System Response

INCLUDE 'NA_ALLG_NOVERARBEITUNG' OBJECT DOKU ID TX

How to fix this error?

INCLUDE 'NA_ALLG_MOEGLICH' OBJECT DOKU ID TX
Maintain a network profile in the project definition.
You can also maintain a network profile from time scheduling.

Error message extract from SAP system. Copyright SAP SE.