IP Location issue

I'm in Phx, AZ. I got the original 4G Tmo-HI in Oct 2020. It constantly showed my location, based on my public IP, as being in Los Angeles, CA, somewhere near LAX. That's 400 miles away.

I have a FireTV adapter that I use to access several services, and I get local ads for southern CA, and even political ads for CA. I don't get anything for AZ or the Phx area.

I switched to their 5G modem several months later, and they started building a new 5G tower about 1000 feet from my house. I noticed the public IP would switch between a Phoenix IP and one in the LA area. I talked to someone in their ABQ tech center and was told that once the 5G towers were fully operational, then I'd see Phx-based public IPs all the time.

What has happened is the opposite: all I get now is from a different location in downtown LA that usually shows up as Compton, Anaheim, or just LA.

I've spent several hours on the phone with their so-called "technical experts" in the Philippines, and they just keep saying it's either my equipment or because the system uses dynamic IPs. My equipment is located behind the device and all are assigned 192.168.12.xxx IPs, whether they're connected via WiFi or wired ethernet. My desktop computers are all connected via wired ethernet. And they do NOT have GPS chips in them, so there's no way for them to say what their location is.

Nor does my FireTV device have a GPS chip in it.

I can verify that the public IP address IS, in fact "dynamic" as it does change from time to time. But it's pretty much ALWAYS: 172.58.16.xxx, which is always in SoCal, 400 miles away.

I do not understand why these people refuse to acknowledge that they are doing something that makes the use of GEO-IP worthless.

The only reply I got from them was, "it seems your internet service quality is not impacted by this, so we don't consider it to be an issue." That's true, if you ignore the fact that every eCommerce site I get onto like Best Buy, Home Depot, Lowes, etc, thinks I'm located in a 900xx zip code in LA County.

I have tried turning the trash-can modem off and unplugging it and leaving it that way overnight, then restarting it a few times, but it made no difference. My public IP still says I'm in Los Angeles, CA.

I do not understand why this is of no concern to them. I don't buy their argument that it has anything to do with "dynamic IPs" or even that my public IP is assigned "randomly" and "for security purposes". 

I'm not interested in California politics or SoCal businesses or anything like that. I live in Arizona. Why can't they assign me a public IP *SOMEWHERE* in Arizona or in the general Phoenix area?