Hello Himanshu,
Do I understand correctly that the end-system is generating a unique ID on account creation that you then want to fetch and send in a 2nd request?
If this is the case, try to add another “Account Aggregation” operation to your webservice connector and add the “Create Account” operation as a “Parent Endpoint” to the new aggregation operation. This should result in an aggregation event whenever the “Create Account” operation runs.
