Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires phpunit/phpunit ^11.0.0 -> satisfiable by phpunit/phpunit[11.0.0, ..., 11.1.2]. - phpunit/phpunit[11.0.0, ..., 11.1.2] require php >=8.2 -> your php version (8.1.27) does not satisfy that requirement. Problem 2 - digitalrevolution/accessorpair-constraint v2.2.0 requires phpunit/phpunit ^9.0 || ^10.0 || ^11.0 -> satisfiable by phpunit/phpunit[11.0.0, ..., 11.1.2]. - digitalrevolution/accessorpair-constraint v2.1.18 requires phpunit/phpunit ^9.0 || ^10.0 -> found phpunit/phpunit[9.0.0, ..., 9.6.19, 10.0.0, ..., 10.5.18] but it conflicts with your root composer.json require (^11.0.0). - phpunit/phpunit[11.0.0, ..., 11.1.2] require php >=8.2 -> your php version (8.1.27) does not satisfy that requirement. - Root composer.json requires digitalrevolution/accessorpair-constraint ^v2.1.18 -> satisfiable by digitalrevolution/accessorpair-constraint[v2.1.18, v2.2.0].