Message type: E = Error
Message class:  IST_EBS - Interface Between IS-T and External Billing System 
Message number: 188
Message text: Activity &2 is defined for user key &1, not activity &3
A run of activity &2 is defined for user key &1. However the
FKJO_SCHEDULE was called with activity &3.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Check your entries in the FKJO_SCHEDULE report.
Did you specify the correct activity?
If yes, then the activity for the run that is defined for the user key
&1 is probably incorrect.
In this case the function call to FKJO_JC_PARAMS_ADD that took place
earlier in the flow logic is incorrect.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message IST_EBS188 indicates that there is a mismatch between the activity defined for a user key and the activity being attempted. Specifically, it states that the activity you are trying to perform (activity &3) is not defined for the user key (&1) that is currently being used, which is instead defined for a different activity (&2).
Cause: User Key Configuration: The user key you are using is configured to allow only certain activities. If you attempt to perform an activity that is not permitted for that user key, this error will occur. Authorization Issues: The user may not have the necessary authorizations to perform the requested activity. Incorrect User Key Assignment: The user key may have been incorrectly assigned to the user or the activity may have been incorrectly defined in the system.
Solution: Check User Key Configuration: Go to the configuration settings for the user key in question and verify which activities are
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