Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires islandora/islandora dev-github-testing as dev-2.x -> satisfiable by islandora/islandora[dev-github-testing]. - islandora/islandora dev-github-testing requires drupal/core ^10.2 -> found drupal/core[10.2.0-alpha1, ..., 10.4.x-dev] but the package is fixed to 10.1.8 (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.