New Router Keeps Assigning Wrong ip addresses

I recently had an outage and following that connection issues started to happen. I went through the xfinity app and it advised my modem/router was out of date and could not keep up with my subscribed speeds. At "no extra charge" they would send a replacement. So 2 days later my Technicolor CGM4331 arrived and following the prompts from the app it installed seamlessly, or so I thought. This was on a Tuesday on the following Friday at 1:30 am all of our internet went down, sometimes the app would say there was an outage in our area and other times it would say our area was fine but or internet was still off line. Sometime Friday afternoon our internet was restored,(all other wired and Wi-Fi devices were fine), but our main PC would not connect to the internet, (this is a direct ethernet connection). Reboot Modem, blah blah. No change! While reviewing my connections I noticed my ip address for the PC did not have the same prefix as all of my other devices. It was set to "obtain ip address automatically) no mater how many times I rebooted PC or gateway there was no change. I even went to cmd prompt and ip release/renew. Still no change. Giving up in frustration I assigned a static ip address to my main PC that the router would accept and everything was fine.

Now here we are today, when I awoke this morning and picked up my iPad it was connected to Wi-Fi but there was no internet, when I examined the settings I could see that the wrong ip address was now incorrect on my iPad. I contacted CS the stupid virtual assistant forced a reboot of my gateway, after 1/2 hour of that distraction it finally gave me an 800# to call. I was on the phone with them for 2+ hours and nothing is solved.

I see now that my iPhone is doing the same thing, when I look at my "connected devices" list, my iPhone and iPad are listed as "connected" even though the iPad is turned off and the iPhone has the wi-Fi turned off. As a result I can not get the system to "forget" the devices to see if it will reset the license for the ip address.