Hi @maneesh3 

As you mentioned client is sending unique ticket Number, so when ticket is created by email at the same time parse the subject and you can use OOTB field correlation ID where use can store the Jira Ticket number

In your email action script you can easily check if any ticket is created w.r.t Jira ticket Number and accordingly you can create or update new tickets

Thanks,

Vijay Balotia

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Thanks
Vijay Balotia