Device payment plan

I’m beyond frustrated, I’ve been told by xfinity if I upgrade to the premium unlimited and trade in my phone, I can get the iPhone 17 practically for free… well when I went to the store to try and take advantage of this I was denied due to a freeze I placed on my credit reports… so I lifted the freeze and tried again, denied… they told me to give it 24 hours and to try again, well it’s been 9 DAYS and they still want me to pay in full… I have expressed my frustrations with them and they told me to “wait” it out and there’s nothing they can do…. I have a flawless payment history and my credit score is near the 800s…. Why am I paying more for a phone plan when I cannot use the benefits that come with it? I’m at a loss and honestly might have switch phone providers if this does not get resolved asap.