Is there a way to format a subject line to automatically add an issue to an existing project. For example I can update a specific JIRA item with [JIRA] (DE-732) CRM Submitted Provider Updates, but is there a way to do the same for a project.
I recommend reading over the Atlassian doc on Mail Handlers. It sounds like you already have a generic "Comment" mail handler configured. When you reply to a notification from Jira, the email is sent to a mailbox that Jira checks. When it sees the issue number in the email Subject, it adds a comment to that issue.
When you want to create new issues, you either need a "Create new" or a "Create new and Comment" mail handler. Each is configured for a single Project in Jira and requires a dedicated email account (mailbox) that it checks.
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