Liberty Life Refund debacle

We cancelled my Wife's Retirement Annuity as her business took a nosedive. This was cancelled but the person who assisted us forgot to cancel the debit order. As a result the debit order amount of R732 came off from a bank account that has no funds. The bank subsequently charged us a fee (R250) for honouring the debit order. After some calls and emails we were refunded the debit order fee of R732. We highlighted that as the debit order was not cancelled, Liberty is liable for the bank charges. After numerous emails and calls we were told that the bank charges will be refunded. This refund has not materialised. We called and emailed Liberty almost daily. The last communication was that we need to send bank statements which we did and then we were told to send a bank stamped statement. At no point was this highlighted. I find this level of service unacceptable.