1) Why do you say that the information was incorrect?
If you rented out your property, the lender would be entitled to put you on BTL rate. It might depend on the lender but I suspect that most mortgage agreements allow them to do this. In practice, they might not enforce it. But I don't think you can argue that it was incorrect.
2) If you own only one property, even if it is rented out, you are entitled to the protection of the CCMA. But did the bank tell you that you were not?
Brendan