Diagnosis
In event R964 (creating a pseudo-mandatory group using several optionalcontracts), you selected different optional contracts for which you wantto create a joint budget billing plan.
However, contract &V1& is either a mandatory or exclusive contract.
You can only select optional contracts to create a joint budgetbilling plan.
INCLUDE ISU_VERARB OBJECT DOKU ID TX

Procedure
Either change the Joint Invoicing indicator in contract &V1& to2, or change event R964 so that contract &V1& is not included inyour selection for the joint budget billing plan.