Invalid Run Mode <&1>

What causes this issue?

You started the Payment Run job with an invalid run mode.

System Response

The Payment run job has been cancelled.

How to fix this error?

The Payment Run job can only be started in the following run mode
N - Normal
R - Restart

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.