Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires friendsofphp/php-cs-fixer 3.43.0 (exact version match: 3.43.0 or 3.43.0.0), found friendsofphp/php-cs-fixer[v3.43.0] but the package is fixed to v3.7.0 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command. Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.