Dear Diane,
unfortunately the time change was due to Duomo Cathedral extraordinary closeure and you were informed accordingly, but you never confirmed us the safe receipt of our email.
For this reason the coordinator did not wait for you and, as per procedure, he asked you a voucher in order to check if your booking was valid or not (oral confirmation, as you may understand, is not enough).
Moreover we remind you that your tour included la Scala Museum and Duomo Cathedral not the rooftops as correctly reported in the tour descriprion: you shall not be surprised not to join something that was not included.
We suggest you for next time to double check all the info received.
Thanks
Best Regards
Davide