While we have the ability to restore them, backup and restore is not a service we officially offer. I've done it before for users, and we routinely make them for people, but we do not guarantee they'll actually work when you need it. We legally have to say this, otherwise someone could sue for data loss.
For example: If we reset your account it'll be overwritten with the state of the account immediately before the reset, if our server's hard disks go bad or we get ransomware (again) we may lose it, etc. We can't guarantee that they will actually be there when you need them, so even though we have a backup, you are expected to also have your own and be able to extract the files and upload them to fix your account if needed.
The easiest way to do this is to simply download the file from https://heliohost.org/backup/ and store it somewhere safe. We can always walk you through extracting it and manually setting up your account if it became necessary,