Some important things to know about WhatsApp backups in Google Drive.
If you’re looking for how to restore a WhatsApp backup, please see this help article. If the backup you want to restore seems missing or has been deleted, only the newest backup is stored, overwriting the previous one. Deleted WhatsApp backups are permanently deleted and cannot be recovered I’m afraid.
In addition, WhatsApp backups that haven’t been updated in more than one year are automatically removed from Google Drive and cannot be recovered.
For more information, visit the WhatsApp help center.