Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires ergebnis/json-normalizer ^4.0 -> satisfiable by ergebnis/json-normalizer[4.0.0, ..., 4.6.0]. - ergebnis/json-normalizer[4.0.0, ..., 4.6.0] require justinrainbow/json-schema ^5.2.12 -> found justinrainbow/json-schema[5.2.12, v5.2.13, 5.3.0] but it conflicts with your root composer.json require (^6.0). Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.