Dealing with Asus Merlin

I have replaced an earlier Asus router (AC66). It would not talk to me. I put in an AC-3100. I wanted better processing and improved WiFi to handle phones in the house. Access was fine, but suddenly I could no longer sign on to the router. I have tried multiple alternatives, with no joy. There appears to be a secret double probation limit to accessing the router.

I went to the Asus site, but that is, as I have always observed, a zoo of of strange. Every time I come back to the Asus site, I...

Dealing with Asus Merlin