Global Pass activated without any notification message from xfinity

I recently traveled outside US and I have been billed for all the days of travel though I had not make any SMS or phone calls and had data roaming disabled. As far as I remember when Global pass is activated I should receive a message notification during start and end but in this case I did not receive any. I noticed similar complaints from other customers. Why is this not fixed? I believe this feature from Xfinity Mobile is probably broken and is not tested. What is the best way for me to get these charges removed?