firmware update and Charte Spectrum

I do appologize if it seams as though I am being derespectful to anyone. But I'm not really sure what the issue is obviously to point. But there are a few. 

1ST I have an I5 gaming computer that is wired. Fresh install and updated. Nvidia drivers. Computer is as old as the combo I bought.  not even a year old.

2Nd When I use speedtest.net my ping is around 8ms, download is 460-ish mbps and upload is just over 20 mbps. I know lightning fast right. I pay for the 400 mbps package. No phone or tv. package. Just internet.

3RD I had a new hub installed on the pole right behind my house and payed to have new co-ax put in. (Been tested by charter and works fine. Better than what I pay for actually with no issues there.)

   My problem is that Charter can't see that I am online. They have a different IP address for me at Charter and I have a different one when I check on my computer. Proved this to a Charter service tech. He watched me do a speedtest as well as watch youtube and check my email etc. But while he was on the phone talking to a Charter rep they said my internet was out. He told the lady that he was watching me surf the web. Told her about the speedtest and everything.  I did a factory reset on my Router/Modem combo while he was here. He even reactivated it and then we were right back to where we started. I've read everything I can find on it. I have never had any browser other than Edge (cause I can't take it off) and google Chrome now. I switch back and forth between Chrome and Firefox. The only program I run on my PC is CCLEANER. No after market anti-virus software either. 

   My lag comes from gaming, Netflix or Amazon Prime movies. Even my youtube acts funny at times. And my PC will be the only thing connected to my combo unit. No one else using it. It also doesn't mater if I am using a PS4 for gaming or a Smart TV (Vizio) for the movies. All in the same room with the router. 

    It sucks because when I first load into any shooter PVP game my ping is super low. Then it jumps really high and stablizes around 80ish. I'll have lag and have packet loss. Movies will buffer. I know some people can understand how frustrating this is.

    No one can explain the 2 different IP addresses. As I'm not running any kind of software. I have never did any dark web activity. Which the Charter rep asked me about. LOL. He did tell me that he knows for a fact that Charter will mess with the throttle on the internet if they thinks something is suspicious. The only thing that I found remotely close is the fact that my modem needed to be updated to another versoin. They have did everything but help me with it. They have avoided it at every turn. 

    And ya, I know that I might have to buy a seperate unit. I told him I was going to get an Aris surfboard 3.1 docsis. He told me that in the last few months out od all the ones he tried to register with charter he was only successful with one. And that was after around ten tries. So ya, Charter does want people to use their equipment. I don't know what they did when they updated their system. But they are obviously having problems also. And I'm not the only one. The Charter rep said that most of his calls were for people having issues and they owned their own equipment.