Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires sylius/sylius ~1.12.0 -> satisfiable by sylius/sylius[v1.12.19, v1.12.20, v1.12.21]. - sylius/sylius[v1.12.19, ..., v1.12.21] require api-platform/core ^2.6 -> found api-platform/core[v2.6.0, ..., v2.7.18] but these were not loaded, because they are affected by security advisories ("PKSA-gs8r-6kz6-pp56", "PKSA-gnn4-pxdg-q76m", "PKSA-dsd6-6541-26zs"). Go to https://packagist.org/security-advisories/ to find advisory details. To ignore the advisories, add them to the audit "ignore" config. To turn the feature off entirely, you can set "block-insecure" to false in your "audit" config.