SAP Message 0T202 - There is already a delivery with the source &2.&3

Diagnosis
You could not include the entry &V2&.&V3& in the target group &V1&,since the system/client combination already exists as the source of adelivery that directly or indirectly leads to the delivery target &V1&.

System Response
You cannot define delivery cycles.

Procedure
Remove the delivery, or use a new target group.