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I saw that you created a ticket with our support and it was already resolved, so I'll share the resolution here in case other community members face the same issue.
It was found in the logs on your instance that there was an error with the Jira Charting Plugin (NoClassDefFoundError), which the plugin was incompatible withing the Jira Server version.
To fix this it's necessary to uninstall Jira Charting Plugin and download from this page the version compatible with the Jira version.
Hi All! We’re excited to share the launch of an announcement banner that lets Jira site administrators communicate directly to their users across their Jira Cloud instance. ...
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