Delete a Yandex.Music account
If you have a Yandex account that you use to log into other services, then you will lose data saved on all the personal services connected to that account (Mail, Disk, etc.) if you delete it. Learn more in the Deleting your account section of Help for Yandex.Passport.
Don't delete your account just to cancel a recurring subscription or stop receiving notifications. You can disable Yandex.Music notifications in the settings of the web version and cancel your subscription at any time. If you purchased your subscription through iTunes, you can cancel it yourself even if you already deleted your account. If you deleted your account and forgot to cancel the subscription you purchased in Yandex Music for web, contact support.