It appear that AT&T has cancelled your non-PDA data plan and is now charging you pay per use. The rate is per kilobyte. You are looking at nearly $260 in charges so far. There should be an effective date for one data plan ending and the pay per use beginning. Call Customer Service immediately, You should have done that before you took time to post in this forum. The meter is running.
Have you made any changes recently on OLAM, with CSRs or in a store? Visited a store where they looked up your account?
It sounds like someone made a change on your account, perhaps accidentally or maybe out of confusion.
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