When you are in router mode the ip to access the shub is 192.168.0.1. When it is in modem it is 192.168.100.1 and that should work for you now. My apologies, I should have told you that before so you didn't panic. You don't have to do a factory reset to get it back in router mode, you can go back in to the shub and afaik the first option you should see is a button for router mode and everything else will be blanked out. It will reset itself which will take a couple of minutes and then all your wifi and everything will be back.
When you have got 10 mins later read each of these links. Take your time and read them properly so you understand the problem and how it applies to you. They are all pretty much the same but go in to varying levels of detail and I always think it is good to understand something rather than just doing it. I wouldn't worry about the fourth link too much, it is just for reference and you should get everything you need from 1 and 2.
https://www.onmsft.com/news/windows-...d-heres-change
https://www.ghacks.net/2016/08/05/wi...nternet-speed/
http://www.tomshardware.co.uk/answer...-hardware.html
https://blogs.technet.microsoft.com/...totuninglevel/