cannot access my modem via the IP address, and I am not getting 150mbps, i capped off at around 90 or so with the 300 mbps promo going on
What sort of troubleshooting have you done so far? For example, have you tried power cycling the modem? I know it's a bit of a cliche but it's worth a shot if you haven't done so already. If you need to check if the modem is bridged, I'd recommend getting in touch with customer support as they can check that for you.
Capped at 90 or so? 95 mbps? Usually means a wired connection that is connected at 100 mbps for some reason.
Bad cable? 100 mbps switch connected? Computer forced to 100 mbps for some reason? Or it is older and doesn't have a gigabit network adapter..
If wireless, there are a lot of other issues that could be going on, but wired at 100 mbps is most likely without more information.