@Carter H Thanks for reaching here! When an email is added to the suppression list that mean we receive a hard bounce from the recipient server, and the sender need to understand why their email hard bounced (One of the top reasons is that the sender is missing MX record while the receiver expect one). Then you need to work on fixing it.
From ACS public documentation Improve sender reputation in Azure Communication Services email - An Azure Communication Services concept article | Microsoft Learn: -
- Initial suppression: When Azure Communication Services encounters a hard bounce with an email address for the first time, it adds the address to the managed suppression list for 24 hours.
- Progressive suppression: If the same invalid recipient email address reappears in any subsequent emails sent to the platform within the initial 24-hour period, it's automatically suppressed from delivery, and the caching time is extended to 48 hours. For subsequent occurrences, the cache time progressively increases to 96 hours, then 7 days, and ultimately reaches a maximum duration of 14 days.
- Automatic removal process: Email addresses are automatically removed from the managed suppression list when no email send requests are made to the same recipient within the designated lease time frame. After the lease period expires, the email address is removed from the list. If any new emails are sent to the same invalid recipient, Azure Communication Services starts a new cycle by making another delivery attempt.
- Drop in delivery: If an email address is under a lease time, any further mails sent to that recipient address are dropped until the address lease either expires or is removed from the managed suppression list. The delivery status for this email request is Suppressed in the email logs.
Note- To remove the email from the suppression list manually, You needs to open a support ticket.
Also, Reached you privately.
Please let us know if you have further query or issue remains.