Hello,
Thank you for contacting us regarding deleted Softaculous Backups. I recommend reviewing the server logs for record of the backup being deleted. If you are on a shared server, Live Support can assist you with this. This will provide specific clues and evidence into what happened. It will also allow them to provide account specific information in a secure setting.
If you have any further questions, feel free to post them below.
Thank you,
John-Paul