We were recently surprised to receive a bill for $944 worth of excess internet usage. Excess usage? We're supposed to be on the unlimited Go Large plan. I immediately called and was told it would be resolved and a credit placed on the account, so this wouldn't be so much of a problem except yesterday was the due date for the month's bill, and we have a direct debit set up. Goodbye $944 -- the credit hadn't gone through, it was still "in process", apparently. Noone I could get hold of at xtra was much help, "it's with another department" they said. Here's hoping we'll get the money back soon.
The irony of the situation is some time ago I wrote an application to make it easy to check your usage, used by hundreds of people in NZ. If only I'd used it myself! (like I used to when I knew I had a traffic limited account).