ERROR ITMS-90685: CFBundleIdentifier Collision. There is more than one bundle with the CFBundleIdentifier value 'XXX' under the iOS application 'Y.app'. about fastlane

[Maxim-Filimonov]

Having the same issue. Based on my investigation when update_code_signing_settings is called with bundle_id it would override bundle_id for all targets by default. That means that your extension bundle_id would change.

[hromovp]

In case someone stumbles upon this, as per Maxim-Filimonov comment, removing bundle_id from update_code_signing_settings and using targets instead helped me to resolve this. Here is part of my lane:

  ...
  # app
  update_code_signing_settings(
    path: project.xcodeproj,
    use_automatic_signing: false,
    team_id: TEAM_ID,
    build_configurations: project.build_configurations,
    code_sign_identity: project.code_sign_identity,
    profile_name: ENV[project.sign_profile_name],
    profile_uuid: ENV[project.sign_profile_type],
    targets: [project.target],
  )
  # extension
  update_code_signing_settings(
    path: project.xcodeproj,
    use_automatic_signing: false,
    team_id: TEAM_ID,
    build_configurations: project.build_configurations,
    code_sign_identity: project.code_sign_identity,
    profile_name: ENV[project.sign_extension_profile_name],
    profile_uuid: ENV[project.sign_extension_profile_type],
    targets: [project.extension_target],
  )

  gym(
    derived_data_path: project.derived_data,
    configuration: project.build_configurations,
    workspace: project.workspace,
    scheme: project.scheme,
    export_method: project.export_method,
    clean: true,
    include_bitcode: false,
    include_symbols: true,
    export_options: {
      manageAppVersionAndBuildNumber: false,
      compileBitcode: false,
      provisioningProfiles: {
        project.bundle => ENV[project.sign_profile_name],
        project.extension_service => ENV[project.sign_extension_profile_name],
      }
    },
  )
  ....