Storm ready 250$ scam

Hi Xfinity team,
I got into new Xfinity WiFi plan June end from then my bill has been on higher end I have been following up with customer service but they were redirecting me back and forth to Xfinity mobile team and Xfinity WiFi team finally one executive said it is due to storm ready device.When I got into new plan the Xfinity store executive talked very kindly telling she will take care of everything get me best discount and got me signed in multiple forms. I checked whenever I need to cancel and go to other place as I’m being student will I be liable to pay anything back she said I don’t need to pay and anytime cancel my service with 0 charges. But today my bill says 250$ with one time charges of storm ready. Being student I’m struggling a lot to earn each penny and paying 250$ for a device is insane and honestly I won’t be able to afford. I need Xfinity officials to take action immediately and help me in this matter.