Custom Web Service Error ISG_SERVICE_EXECUTION_ERROR

Hi Team,

I have developed a custom rest web service in EBS with SOA Integrated Gateway Resp., with the oracle DB. After registered the DB pkg., created my custom web service.

I am invoking it from postman but I am getting following error, I have the grant access to the user also.

{
"ISGServiceFault": {
"Code": "ISG_SERVICE_EXECUTION_ERROR",
"Message": "Error occurred while executing the web service request",
"Resolution": "System error, please see service log trace for details.",
"ServiceDetails": {
"ServiceName": "workReq",
"OperationName": "create_work_request",
"InstanceId": "0"
}
}
}

Any suggestion or tip will be highly appreciated. Also how can I view service log?