Increasing premiums without consent

We took out two policies in 2004 - one for life cover and the other annuity. Both were paid by one debit order. In 2012 - I find that they are increasing the premium for the live cover as well - but not the pay out value. I ask them to cancel escalations to which they agree and they confirm by e-mail 0n 2 Aug 12 that all schedule increases has been cancelled (Amien Adams). on 4 Oct this year, we find that they never cancelled the increases - the premium has escalated from 219 to 318 pm - a total overcharge of 4170.29 for the period, including interest. I have asked them to reduce the premiums back to R 219 and to refund. All they do is submit new quotes to me (Non explanatory) and they refuse to refund. The very last response was a copy of the original document signed with the insurance broker in 2004 - stating they are acting in good stead. I have already agreed that I have been misinformed by the broker in 2012 - hence me accepting to keep the premiums at 219. Their acceptance of this agreement nullifies the original broker document. I have reported this to the Old Mutual ethics department [Email Removed] but they did not even acknowledge receipt.