My wife vs Cox employee

My wife register COX TV, Internet 6 month ago. She told me monthly fee is $90 so I agreed to use COX service.

However, this month honorable COX take $101 from my BofA account.

So I and my wife went cox office in Irvine. He said that low price was promotion price and the promotion expired last month.

Oh~ man!!!

My wife said he did not tell her about that.

I am really wonder which one is correct.

My wife did not understand what he was saying? or He did not tell about the expiration?

Next June I am supposed to leave USA. I really hope another promotion which I do not know will not expire.

COX is flourishing month by month due to expriation of promotion.