I've found that there is attribute END_USER_REGISTRATION_REQUIRED in output of command '3scale service show' and it should not been there because of THREESCALE-5542
$ 3scale service show _remote_ 966 ID NAME STATE SYSTEM_NAME * END_USER_REGISTRATION_REQUIRED * BACKEND_VERSION DEPLOYMENT_OPTION SUPPORT_EMAIL DESCRIPTION CREATED_AT UPDATED_AT 966 service2-kp0o incomplete service2_kp0o * (empty) * oauth hosted admin@3scale.ga.net service2 desc 2021-11-16T13:50:14Z 2021-11-16T13:50:15Z