File a formal complaint

My family, and I switched to Xfinity mobile roughly 3 months ago. I ordered my wife a new phone on September 30th, which was back ordered. So the phone just arrived yesterday, but they sent the wrong color phone. Even-though the phone representative verified the phone color backed me verbally as I was placing the order. As it turns out, the representative placed the order wrong. My wife was on the phone for over 3+ hours and was told multiple “Solutions” which included driving to our local xfinity store to blow 2 more hours there. All to be told “There's nothing we can do.” They lied about the iPhone on us. It is NOT on Xfinity. I am paying for it monthly now. To top it all off they told me I needed to upgrade to premium to get the phone “on us”. So they upgraded her line to premium making our bill more expensive for literally no reason since I am apparently paying for the iPhone. And I have to pay it overtime monthly. None of this is our fault and my wife and I are so disappointed with not only the phone but the entire experience. I just keep thinking, “Why did we even upgrade her phone? If we aren't going to get what we asked for and what was advertised as I'd mentioned previous, then what is the point of being with Xfinity.”  I've been very displeased with the services. I work long hours and cannot always get an opportunity to call. So I let a lot of things slide, but enough is enough already. I’ve spent countless hours on the phone with no resolve. I’ve been disconnected by agents on chat. The list goes on and on. If xfinity cannot be accountable and actually provide solutions for the problems I am having with their services, I will be forced to go elsewhere and at this rate, it will probably even be cheaper for me to do so… Again, the fact that my wife blew almost 12 hours out of her day on the issue with her new phone to have no resolution is not okay with me nor should it be okay with xfinity. If this is how Xfinity “handles” their problems, I have no interest staying with them.