There are multiple RuneMate accounts showing under your IP address. Multiple accounts will combine hours.
Tutorial - Billing and Payment FAQ
My brother/sister/other uses RuneMate in my house, will our hours combine?
Yes. Hours used across multiple RuneMate accounts from the same IP address will combine. EG: Account001 uses 10 hours on a Monday; these 10 hours will also show up on Account002's usage history for Monday.
Why are my hours disappearing so quickly? I haven't used that many hours?
You are likely on a shared network or using a VPN where someone else on your network has used up the hours. If this is the case you should speak to your service provider and ask them to give each connecting user a unique public IP address.