Is a bank negligent in not informing the borrower of the change in prime rate?

The bank was in a fiduciary relationship with the plaintiffs; the plaintiffs relied on the bank for advice in regard to their financial dealings, the debiting of the plaintiff's account in payment of interest charges as well as payments on principal, and in the calculation of interest charges. The bank was aware that at no time were the plaintiffs given information as to the prime rate or the actual rate they were being charged, and the bank was therefore negligent in not obtaining new promissory notes at the changed rate. The bank's negligence in failing to notify the plaintiffs firstly of the fact that the bank was charging them interest at the rate of prime plus 2.75%, and secondly, of the changes in prime rate as it changed from time to time, (and hence in the rate being charged) created the situation where on the bank's demand, the plaintiffs were compelled to pay off the entire amount owing on their loans together with the excess interest charges under a practical, although not legal, compulsion to pay. I find, however, that the bank believed it had the right to charge interest on the basis of a floating rate, although this was a mistake in both fact (because I find no agreement to this effect) and law. The bank had no right to payment of the interest charges in excess of 10 3/4% per annum, and the plaintiffs are entitled in the circumstances of this case to repayment of these sums together with interest. The bank was aware (having full knowledge of the plaintiffs' financial situation) that the plaintiffs would have to borrow money in order to satisfy the bank's demand for payment: O.L. Knutson v. The Bourkes Syndicate et al., 1941 CanLII 7 (SCC), [1941] S.C.R. 419.