Which AX5400 is that?
AX5400 is not a reliable guide to model number. Many devices come with an AC/AX tag, but it is essentially a label that Netgear, and other brands, attach to hardware to describe wifi speeds.
Look at the label on the device for the model number.
Having lots of issues trying to connect to my most used sites, won't let me connect on any of my PC's or Laptop
Connecting how? On what?
What happens when you try?
Troubleshooting depends on having detailed descriptions of what you are doing, what goes wrong, and what you have tried to fix things.
What firmware version do you have on the device?
A number is more useful than "the latest". (It may not be by the time people read this.) There can also be newer versions, or "hot fixes", that do not show up if you check for new firmware in the browser interface.
It might also help if you told people what the modem is in front of this router, if there is one. The make and model number could be useful. Is it, by any chance, also a router, with a set of LAN ports on the back?
The reason for asking is that a lot of people turn up here trying to put a router behind a modem that is also a router. That can complicate troubleshooting.
Just another user with a set of boilerplate macros.
My network DM200 -> R7800 -> GS316 -> PL1000 -> Orbi RBR40 -> Orbi RBS50Y -> RBS40V
