Fatal error: Uncaught Error: Interface "Composer\Plugin\PluginInterface" not found in /home/amper418/shopv2.amperio.ch/vendor/symfony/flex/src/Flex.php:53 Stack trace: #0 {main} thrown in /home/amper418/shopv2.amperio.ch/vendor/symfony/flex/src/Flex.php on line 53