Xfinity app and website suddenly saying "internet offline"...But I have internet

Hello,

Earlier today my internet went out for 15 minutes. When it came back online the Xfinity app and the website both say that a modem is not connected and that I am offline. The internet is working fine though. I have an Arris SBG10 for reference, and it was setup back in early January with no issue until now. What could have prompted both the app and the website to not recognize this device anymore?

Thanks!