Fatal error: Uncaught Error: Interface "Psr\Container\ContainerInterface" not found in /var/www/html1/wp-content/plugins/zettle-pos-integration/vendor/dhii/collections-interface/src/ClearableContainerInterface.php:10 Stack trace: #0 {main} thrown in /var/www/html1/wp-content/plugins/zettle-pos-integration/vendor/dhii/collections-interface/src/ClearableContainerInterface.php on line 10