If this is a Bitbucket Server instance (for example, the address is something like bitbucket.yourcompany.com), you'll need to work directly with the server administrator to resolve the issue. It's likely there's something amiss with the mail server configuration - potentially a blocked firewall port or an expired SSL certificate.
As an alternative, if your team is on a chat platform, you could install and use one of the Slack connectors or Microsoft Teams connectors to get PR and other notifications directly in your chat client. The options for most connectors let you fine-tune which events you'd like notifications for, and choose if you'd like notifications to go to a channel or to you directly via private message.
Hey Community! We’re willing to wager that quite a few of you not only use Bitbucket, but administer it too. Our team is excited to share that we’ll be releasing improvements throughout this month of...
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