I can't delete my account
There's no need to delete your account if you just want to get rid of your data on one of the Yandex services: you can do this in your account settings. For more information, see Delete data. You can delete unwanted photos, clear your spam folder, or change the answer to a security question that you've forgotten using the service that stores this data. You can find a solution to your problem with that service in Help. They're all listed on the main Help page.
Alert
All your data from Yandex services (for example, Yandex Mail emails or files on Yandex Disk) will be deleted along with your account. This data can't be restored in the future. You can create an account using the deleted username only six months later.
To completely delete your account, go to the Data tab and click Delete account at the bottom of the page. You'll have to confirm the action with a code sent to your mobile phone or email address.
If you didn't link either an alternate email address or a phone number, you'll have to answer a security question. If you don't remember this answer, follow the instructions on the I forgot the answer to my security question page.