Yes I'm having the same problem. It's usually due to there being an open order on your account or contract coming up for renewal. In my case my contract is up for renewal in March next year so I don't expect that message to go away before then.
The stupid thing is that, as probably with yourself, I don't give a t*ss about any special offers, I just want the freedom to manage my account as I please but it seems that BT think they know what I want better than I do.
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