C6300 IP problems

I have had this modem for a few years now and it has always worked flawlessly. Today my internet provider upgaded my service and put me on a faster internet plan. Ever since then I can not access my modem/ router and the wifi does not work. The IP listed on my network connection is different from my router IP. For some reason it seems that I am connecting to the IP from my internet provider rather than my router. I can not even access my router from the routerlogin.net. Does anyone have a fix for this issue? I don't know much about networking so I am sorry for my vague and uneducated details.