Amazon SES can not be accessed anymore

Mautic 4.4.3
PHP Version 7.4.33
MariaDB 10.6.17-MariaDB-cll-lve - MariaDB Server

This is the PHP error log:
[21-Apr-2024 05:53:35 UTC] PHP Deprecated: strpos(): Non-string needles will be interpreted as strings in the future. Use an explicit chr() call to preserve the current behavior in /home/dinomadp/mautic.dinomad.pro/app/bundles/EmailBundle/Swiftmailer/Transport/AmazonApiTransport.php on line 383
[21-Apr-2024 05:53:39 UTC] PHP Deprecated: strpos(): Non-string needles will be interpreted as strings in the future. Use an explicit chr() call to preserve the current behavior in /home/dinomadp/mautic.dinomad.pro/app/bundles/EmailBundle/Swiftmailer/Transport/AmazonApiTransport.php on line 383
[22-Apr-2024 08:51:36 UTC] Doctrine\DBAL\Exception: An exception occurred while establishing a connection to figure out your platform version.
You can circumvent this by setting a ‘server_version’ configuration value

For further information have a look at:
BC break between 1.6.7 -> 1.6.8 regarding driver selection · Issue #673 · doctrine/DoctrineBundle · GitHub - in file /home/dinomadp/mautic.dinomad.pro/vendor/doctrine/doctrine-bundle/ConnectionFactory.php - at line 136
[22-Apr-2024 08:51:44 UTC] Doctrine\DBAL\Exception: An exception occurred while establishing a connection to figure out your platform version.
You can circumvent this by setting a ‘server_version’ configuration value

For further information have a look at:
BC break between 1.6.7 -> 1.6.8 regarding driver selection · Issue #673 · doctrine/DoctrineBundle · GitHub - in file /home/dinomadp/mautic.dinomad.pro/vendor/doctrine/doctrine-bundle/ConnectionFactory.php - at line 136
[22-Apr-2024 08:51:51 UTC] PHP Warning - Undefined variable $inline - in file /home/dinomadp/mautic.dinomad.pro/offline.php - at line 77
[22-Apr-2024 08:51:51 UTC] PHP Warning: Undefined variable $inline in /home/dinomadp/mautic.dinomad.pro/offline.php on line 77
[22-Apr-2024 08:51:51 UTC] Doctrine\DBAL\Exception: An exception occurred while establishing a connection to figure out your platform version.
You can circumvent this by setting a ‘server_version’ configuration value

This is the Mautic log :
[2024-04-22 06:35:43] mautic.ERROR: [MAIL ERROR] Error executing “GetAccount” on “https://email.us-east-2.amazonaws.com/v2/email/account”; AWS HTTP error: cURL error 28: Failed to connect to email.us-east-2.amazonaws.com port 443 after 131248 ms: Couldn’t connect to server (see libcurl - Error Codes) for https://email.us-east-2.amazonaws.com/v2/email/account (send); mike@trigon.hu {“exception”:“[object] (Swift_TransportException(code: 0): Error executing "GetAccount" on "https://email.us-east-2.amazonaws.com/v2/email/account\”; AWS HTTP error: cURL error 28: Failed to connect to email.us-east-2.amazonaws.com port 443 after 131248 ms: Couldn’t connect to server (see libcurl - Error Codes) for https://email.us-east-2.amazonaws.com/v2/email/account at /home/dinomadp/mautic.dinomad.pro/app/bundles/EmailBundle/Swiftmailer/Transport/AbstractTokenArrayTransport.php:291)"} {“hostname”:“s54.tarhely.com”,“pid”:4176027}

I have a campaign running from mautic.dinomad.pro domain that sends emails through Amazon SES. However, yesterday (21st April, 2024) it stopped sending emails. I did not change anything, did not upgrade, didn’t touch it. I have no clue what caused the error.

Steps I have tried to fix the problem :
I tried to change PHP version to 8.3, but Mautic 4.4.3 only works on PHP 7.4 (Mautic is installed through Installatron).