I am away on a work trip for three months. No one is at home. I'm not renting it out at all. Recently, I checked the Telus app, and my home internet shows usage of 1800 GB. This makes no sense to me. I even got my parents to unplug all my Telus machines, and the data usage increased by 100GB/ day. Called Telus but no help. This is not normal. last month's bill was 2000 GB used when I wasn't at home either.
Typically the Telus hardware (ie Optik) won't count towards data usage and it won't use that amount of data per day. If no one is using the internet at your house, and your computers are all shut off, have your parents unplug the wifi router. Is there a chance anyone else is connected to your wifi? Do you have IP cameras that may be remotely monitored? If any computers are turned on still, do you know if there is any malware on any of the home computers, or possibly torrents running?
If everything is unplugged, it may not hurt to reach out to tech support when you return home. There shouldn't be any data use showing up with the router / gateway unplugged. 2-3TB of data monthly is a huge amount. There is a small possibility it's a glitch on Telus's end.