How to delete the SMS backed up by Lenovo Mobile Cloud Service completely?

Just cancel your cloud backup account.

Otherwise, it is generally necessary to log in with a computer to completely delete it.

If you don't mind backing up to the cloud.

You can choose to back it up on your computer.

Just download a pc version of AppBao software.

Start debugging after connecting the mobile phone, and use the data in the software toolbox for backup.

This is backed up on the computer, so it is convenient to manage your backup.

hope this helps