I have a Deco M5. Model number shows AC1300, which not an option on your drop down menu, neither in US or Mexico versions. version US 3.0. Problem is that it is blocking access to the main U.S. Social Security Administration website. Apparenly ONLY that site is blocked. I've been using it otherwise without problems for a couple of years.  The master router/wifi to which the Deco connects DOES load that URL. Only when I link to the Deco does it refuse to load. It doesnt show up on the parental list nor on the antivirus. Bizarre.