Create a service package for external operation & &

What causes this issue?

You have planned that a service package should be created for operation
&V1& &V2& <DS:GLOS.control_key>(control key)</>.

System Response

The system has defined that no service package has yet been created for
this operation. For external operations, it is imperative that a
service package is created before the order is saved.

How to fix this error?

Create a service package for the operation, or change the control key
for the operation.

Error message extract from SAP system. Copyright SAP SE.