Ring Alarm Pro hijacked my Centurylink internet connection

I had to reboot my modem. Of course for those couple of minutes the Ring Alarm Pro AT&T internet kicked in. However, the Ring Alarm Pro internet (eero6) never released the internet connection and I was connected to AT&T for several hours. Not only that, but it took over all my ethernet wired devices like my desktop and laptop computers. So when I ran speedtest it showed the host was AT&T for both wired and wifi devices. In order to get my Centurylink connection back online I had to totally disconnect the Ring Alarm Pro and remove the internal battery. Only then could I break the AT&T connection, and access my Centurylink modem. What is the deal? Is the Ring Alarm Pro supposed to send its internet signal downstream to all wired devices??