Process &1 &2 has no successor for option &4

What causes this issue?

Process &V1& &V2& ends with option (event number) &V4&. In the process
chain definition, no process has been defined to start with the event
parameter &V3&, event number &V4&.
There are processes that are waiting for other options however.

System Response

The event will not be triggered. The error will be logged.

How to fix this error?

Adjust the design of the process &V1& &V2& so that it is not possible
for it to end with option &V4&, or change the process chain definition
by scheduling a process that waits for option &V4&.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.