Unable to send test email with PHPMailer

Hey hope you doing well,

I am trying to add amazon SES to the plugin and when i choose mailer type to be PostSMTP it works great when i try to test the mail via the plugin.

When i change mailer type to PHPMailer and try to send a test mail with the plugin i get this error (regular email sent are working well the problem is only with the test mail)

[24-Mar-2022 14:07:02 UTC] PHP Fatal error: Uncaught Error: Call to a member function getCode() on null in C:\wamp-new\www\domain.co.il\wp-content\plugins\post-smtp\Postman\Postman-Send-Test-Email\PostmanSendTestEmailController.php:267
Stack trace:
#0 C:\wamp-new\www\domain.co.il\wp-includes\class-wp-hook.php(307): PostmanSendTestEmailAjaxController->sendTestEmailViaAjax(”)
#1 C:\wamp-new\www\domain.co.il\wp-includes\class-wp-hook.php(331): WP_Hook->apply_filters(”, Array)
#2 C:\wamp-new\www\domain.co.il\wp-includes\plugin.php(474): WP_Hook->do_action(Array)
#3 C:\wamp-new\www\domain.co.il\wp-admin\admin-ajax.php(187): do_action(‘wp_ajax_postman…’)
#4 {main}
thrown in C:\wamp-new\www\yydevelopment.co.il\wp-content\plugins\post-smtp\Postman\Postman-Send-Test-Email\PostmanSendTestEmailController.php on line 267