We have had Onestream fibre for a year, and have recently got ourselves a new router, the Archer AC1200. 

I can't seem to get this connected to the internet. i am able to access therouter though. I thought to copy the MAC settings from the previous router but unfortunately I have lost the login for the old router as it was saved in my passwords and I've saved over that with the new one. I don't want to restore factory setting on that one just yet as it's still a reliable connection we need. 

Anyone have any advice?