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Navigate to the Backup Projects for Jira on your Jira instance and Click to login
Ensure that you have already added your API token and set your email address. If you have not, see the below documents respectively
Step 2
Navigate to the notification Notifications page on the left menu bar and select the usage and preferences tab
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Choose one of the options which inform old messages based on “x” number of days will be deleted.
Subsequently, you can click on the delete icon for each message to delete at will.
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Note
If you have too many unread messages, you can navigate to the user preference and enable the button that mentions “mark unread messages as read” → that this would enable all unread messages to be read to reduce the clutter of notifications.