Global pass deceptive travel charges

Hi- I just returned from an international trip and was charged $482 by Xfinity Mobile, despite having purchased a global pass during the trip (which was an additional $50 at $10/day). Through the trip I got several messages saying my global travel pass was active. Once I landed I noticed that I was charged $482 during the trip. When I called customer service, they said that its because I used data during the flight. First of all most cell service doesn't even work on the flight, so it most probably got triggered during take off or landing. Secondly, I never even got any messages that my global pass is not working and that I suddenly switched over to pay as you go roaming. This is completely unfair and deceptive.

I called Xfinity customer service and they said its in the fine print in the contract. How would someone traveling know that global pass which they paid for suddenly stops working arbitrarily and get switched to a pay as you go at $5 per MB (No messages or alerts were sent). Why would I pay to use 95MB at $5/MB when I can buy wifi on the plane for $20. 

I am absolutely blown away by the level of dishonesty and lack of professionalism from the customer service, I can't believe a big company like Xfinity would engage in this kind of bait and switch and price gouging. We have been loyal customers with 4 lines for the last 4 years, and I am terribly disappointed by this. I feel like I got scammed by this company.