Fatal error: Uncaught Error: Class "JsonSchema\Constraints\Constraint" not found in /var/www/crm_killing_ninja/vendor/justinrainbow/json-schema/src/JsonSchema/Constraints/CollectionConstraint.php:20 Stack trace: #0 {main} thrown in /var/www/crm_killing_ninja/vendor/justinrainbow/json-schema/src/JsonSchema/Constraints/CollectionConstraint.php on line 20