Failure to deliver what was ordered

Hello, I have been a Comcast customer for probably 20 years and the customer service is horrible. You can never talk to a person.   My story begins when I upgraded my Internet package and as a result, I was supposed to be promised a XB10 router I never got that router I have since been through now  three all XB8 models.  I have even had a technician out to my house who never picked up on the fact that the current router cannot handle the speed of the Internet, and as a result, it’s been finally diagnosed that I’ve had fluctuations not hooking up to my pods, which I even purchased an additional one and it does not work because the router is confusing due to the Upscale of the package which now Affects my business in the home. The chat service is horrible. You can never get a live operator and when you do, it’s almost an hour into the automated response and menu.  I’m told different information as such that I have to Go to a Comcast store to get the XB10 modem.  The store tells me they don’t stock that the chat service tells me they don’t mail that.. I am so frustrated with Comcast. I tried to call the store. You can’t talk to anybody. It goes right into the chat.  I’ve paid for something for three months now it doesn’t work correctly and cannot get it rectified I’m at the end where I’m going to just file complaints with a Better Business Bureau and keep filing away because this is just really hitting home.  And Comcast is pretty much the only game in town in my area and they know that I’m just asking to give me something that I pay for and that XB 10. Modem was in with the package that I purchased.    I’m about ready. I have an appointment today at the store and I know when I get there they’re gonna tell me they don’t have this item in stock.   So now what I do, I’ve got one that they sent me which is identical to the one that I have already hooked up, which is the XB8.  Which is been diagnosed by Comcast to finally be the issue   Someone please help