Fatal error: Uncaught Error: Class 'Postmark\PostmarkClientBase' not found in /home/app/htdocs/ninja/vendor/wildbit/postmark-php/src/Postmark/PostmarkAdminClient.php:13
Stack trace:
#0 {main}
thrown in /home/app/htdocs/ninja/vendor/wildbit/postmark-php/src/Postmark/PostmarkAdminClient.php on line 13