Problem
Since the Connector uses an Integration user to make changes in Jira, it requires an active account. If this is deactivated, the integration, although configured properly, won’t be able to create or synchronize information from Salesforce to Jira because the integration user can’t create or modify anything on Jira.
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Solution
Confirm who’s your integration user by going to Jira → Apps → Salesforce → Settings and confirm who the user is. You can refer to the image below for this:
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This should fix the issue, if the issue persists, please get in touch with Support.