Your requirements could not be resolved to an installable set of packages. Problem 1 - phpunit/phpunit[7.1.0, ..., 7.5.20] require php ^7.1 -> your php version (8.1.27) does not satisfy that requirement. - Root composer.json requires phpunit/phpunit ~7.1 -> satisfiable by phpunit/phpunit[7.1.0, ..., 7.5.20].