This page will help helps you configure the mappings to allow Connector for Salesforce & Jira to assign a different user to a created issue.
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Go to Settings > Apps, and then in the sidebar, under Salesforce, choose Bindings.
Choose your desired Bindings, then click Mapping.
On the Mapping Configuration screen, choose the Issue Type you would like want to configure.
For this example, let's choose Task.Then, click on Click Mappings.
The Task to Case field mappings dialog box appears.
In the Jira Field, choose Reporter, and in the Salesforce Field, choose Owner ID.
Then clickClick + Add.
Once you've clicked the + Add button, click on Map Values.
In Reporter field, add the username of the account you want to add.
For the Salesforce Fields Value, you are required to obtain an 18-character Owner ID.
To get this, write down your 15-character User ID from your Salesforce profile URL:
Use this tool to make the conversion of the User ID.
Copy the converted ID, paste it under the Owner ID column, click + Add, then click Save.
Warning Make sure you paste or key in the Salesforce ID exactly as generated, with the correct case (this ID is case-sensitive). and with no spaces before or after the value. For example, 00590002fBnyAAEis not the same as00590002fbnyaae.
In Salesforce, create a new case assigned to the designated owner, where the Owner in Salesforce is using the admin username that has already been mapped in Jira.
Create a Jira Issue from Salesforce.
Back in Jira, you should now be able to see the admin user instead of "Salesforce & Jira Cloud Connector" as the Reporter.
Now, let's change the owner of the case to ensure the add-on can synchronize with the Reporter field.
Go to Salesforce and change the Case Owner.Go back to Jira and Pull the updated changes made in Salesforce.
You should now be able to see the new changes.
The user must be manually mapped as well.