An Error about 'LOY Processing Engine' when a Loyalty Transaction is processed

 Hi Experts,  When attempting to process a transaction with the Loyalty Realtime engine the following error occurs.

ERROR

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Error (null) invoking method "(null)" for Business Service "(null)"

Error invoking service 'LOY Processing Engine', method 'SubmitObjectForProcessing' at step 'Invoke Submit Object'.

The Error happens when Process button in UI is clicked.

Is there anything wrong with the parameters of this engine?

Appreciate your help if you could provide any pointers/solutions.

Thanks and Regards,

Daniel Deng