Disney Cirlce App shows that my router R6400 (AC1750) should have circle on my router. When I try to connect via App it says "Darn, couldn't find circle on your Router."
There exist at lest two different hardware versions - R6400(v1) Model R6400-100xxx vs. R6400v2 Model R6400-200xxx. Only the later one does support Circle in my opinion. Check your router product label. In case it's a R6400v2, ensure you have the current firmware in place - see https://netgear.com/support/
