Unable to email Invoices and Estimates

I'm having issues sending invoices/estimates from Akaunting on an EC2 Instance through AWS SES.

SES is configured correctly and test emails send without error.

Akaunitng has been configured with the correct SES endpoint and creed trials but I get this error in debug when trying to send an accounting invoice.

The EC2 Instance firewall settings for SMTP on 25, 465 and 587 also appear to be correct.

Any help would be appreciated. Thanks.

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Connection could not be established with host email-smtp.ap-southeast-2.amazonaws.com :stream_socket_client(): unable to connect to tcp://email-smtp.ap-southeast-2.amazonaws.com:465 (Permission denied)