SES SNS duplicate notification with different messageID but single email

I've set up SNS with SES and while looking at my logs, I'm seeing duplicate entries for open events but with DIFFERENT messageids, despite only a single email. I am able to verify that it's a single email because I've tested it by sending an email to myself, but moreover, in the logs, the timestamps are almost the exact same time (off by milliseconds). The one interesting thing is the ipAddress is slight different (one ends with .211, and the other with .219)

I've attached the record log below of two OPEN records from the same recipient.

{'EventSource': 'aws:sns', 'EventVersion': '1.0', 'EventSubscriptionArn': 'arn:aws:sns:us-west-1:12345678765:topic_name:c765a5cf-06cf-44d8-afdc-28b63033c949', 'Sns': {'Type': 'Notification', 'MessageId': '1123745b-e254-5168-962b-2e6f2e7ac2fb', 'TopicArn': 'arn:aws:sns:us-west-1:12345678765:topic_name', 'Subject': 'Amazon SES Email Event Notification', 'Message': '{"eventType":"Open","mail":{"timestamp":"2021-12-16T03:12:53.124Z","source":"redact","sendingAccountId":"12345678765","messageId":"0111017dc13a7384-bd1cf759-6814-418c-bd29-6f981a451a2e-000000","destination":["destination@gmail.com"],"headersTruncated":false,"headers":[{"name":"Date","value":"Thu, 16 Dec 2021 03:12:53 +0000"},{"name":"From","value":"redact"},{"name":"Reply-To","value":"redact"},{"name":"To","value":"destination@gmail.com"},{"name":"Message-ID","value":"<321132367.51541.1639624373206@ip-10-0-33-160.us-west-1.compute.internal>"},{"name":"Subject","value":"subject line"},{"name":"MIME-Version","value":"1.0"},{"name":"Content-Type","value":"text/html; charset=UTF-8"},{"name":"Content-Transfer-Encoding","value":"quoted-printable"}],"commonHeaders":{"from":["redact"],"replyTo":["redact"],"date":"Thu, 16 Dec 2021 03:12:53 +0000","to":["destination@gmail.com"],"messageId":"0111017dc13a7384-bd1cf759-6814-418c-bd29-6f981a451a2e-000000","subject":"subject line"},"tags":{"ses:operation":["SendTemplatedEmail"],"ses:configuration-set":["topic_name"],"ses:source-ip":["redact"],"ses:from-domain":["b.com"],"ses:caller-identity":["caller_id"]}},"open":{"timestamp":"2021-12-16T05:09:02.500Z","userAgent":"Mozilla/5.0 (Windows NT 5.1; rv:11.0) Gecko Firefox/11.0 (via ggpht.com GoogleImageProxy)","ipAddress":"0.0.0.211"}}\n', 'Timestamp': '2021-12-16T05:09:02.554Z', 'SignatureVersion': '1', 'Signature': 'e1swVjH1PFog/9syhhDOvS6BgNZnI3RN6k+fRfkXUaUXfmsiy2kAJ+ozKUi9BlnLRtCMnnxRH2GEV6w6t2C4WjWi/IBYr+YUn5veiZtAyQYG/NYgZhCM6yqvfIpfog2wPC3cc0tXj2oehZo8OXj8YvCbz3i8LR+wXn6lNewitJiYNX0yOVzCAWH6xd0QFlNULTk3RYNarM/a5ZmRXil35fhGWsDJnGWjNC5r32WXJB9eAZANpoNMiX/dbUxZTLWqolRGqC3M+JH3qjl/Cy/JSu+pWbSN/mtl/RzLD6W2fZBRtbApHTT+BoRi+x4hz/W6kl5FVUvl3NiSAiZsFQ4DoQ==', 'SigningCertUrl': 'https://sns.us-west-1.amazonaws.com/SimpleNotificationService-7ff5318490ec183fbaddaa2a969abfda.pem', 'UnsubscribeUrl': 'https://sns.us-west-1.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-west-1:12345678765:topic_name:c765a5cf-06cf-44d8-afdc-28b63033c949', 'MessageAttributes': {}}}

{'EventSource': 'aws:sns', 'EventVersion': '1.0', 'EventSubscriptionArn': 'arn:aws:sns:us-west-1:12345678765:topic_name:c765a5cf-06cf-44d8-afdc-28b63033c949', 'Sns': {'Type': 'Notification', 'MessageId': '39179993-647d-521d-ab77-c3a7a853b700', 'TopicArn': 'arn:aws:sns:us-west-1:12345678765:topic_name', 'Subject': 'Amazon SES Email Event Notification', 'Message': '{"eventType":"Open","mail":{"timestamp":"2021-12-16T03:10:32.670Z","source":"redact","sendingAccountId":"12345678765","messageId":"0111017dc1384ede-364355c2-5014-4940-a863-a811402771c1-000000","destination":["destination@gmail.com"],"headersTruncated":false,"headers":[{"name":"Date","value":"Thu, 16 Dec 2021 03:10:32 +0000"},{"name":"From","value":"redact"},{"name":"Reply-To","value":"redact"},{"name":"To","value":"destination@gmail.com"},{"name":"Message-ID","value":"<240748958.52874.1639624232756@ip-10-0-99-60.us-west-1.compute.internal>"},{"name":"Subject","value":"subject line"},{"name":"MIME-Version","value":"1.0"},{"name":"Content-Type","value":"text/html; charset=UTF-8"},{"name":"Content-Transfer-Encoding","value":"quoted-printable"}],"commonHeaders":{"from":["redact"],"replyTo":["redact"],"date":"Thu, 16 Dec 2021 03:10:32 +0000","to":["destination@gmail.com"],"messageId":"0111017dc1384ede-364355c2-5014-4940-a863-a811402771c1-000000","subject":"subject line"},"tags":{"ses:operation":["SendTemplatedEmail"],"ses:configuration-set":["topic_name"],"ses:source-ip":["redact"],"ses:from-domain":["b.com"],"ses:caller-identity":["caller_id"]}},"open":{"timestamp":"2021-12-16T05:09:02.441Z","userAgent":"Mozilla/5.0 (Windows NT 5.1; rv:11.0) Gecko Firefox/11.0 (via ggpht.com GoogleImageProxy)","ipAddress":"0.0.0.219"}}\n', 'Timestamp': '2021-12-16T05:09:02.489Z', 'SignatureVersion': '1', 'Signature': 'VUVBiM+AiCrfdjhZROCI2C3CnYiHD0fa/l8JK5adqnwTXauCZ83Ee/TFZXTXlXk9kweErI5n7ogbHDfe7nvTCjUuQ89I7WM1otU1xW7jkgxInSRTB4QrZl9FFhRUXQ5YiAlYJzhx3gB8+lD46hcQ2vGpRZ8IMPIpo7cnmryeBJxDHJg6ulQL+KWllrJVe8FHWjB5PeCxBHSl3+KWdmjVpakkF45pOpURXhuhVLtgUIP81AUM1510WtJhgKGvc1k1upUrLGHfWnsWe/qRCq+FJ4TdPvbokyGX/TahaSiBQYfgW9GhhRDWTjz5ebYdV9DZeIaJ7zPm0ep+2BYuHhYt4Q==', 'SigningCertUrl': 'https://sns.us-west-1.amazonaws.com/SimpleNotificationService-7ff5318490ec183fbaddaa2a969abfda.pem', 'UnsubscribeUrl': 'https://sns.us-west-1.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-west-1:12345678765:topic_name:c765a5cf-06cf-44d8-afdc-28b63033c949', 'MessageAttributes': {}}}

Anyone have any clue what I'm doing wrong to cause this?