Nedbank Life Assurers ruining my financial life

My wife and I have a home loan that has been running for ten years with Nedbank. In 2017 my wife wanted to add a life cover/ assurance to the account by ceding her Old Mutual Life cover, but she first needed to increase the cover amount. Coincidentally Nedbank Life called her at about the same time offering to provide her with life assurance on the bond amount. She explained to the agent what steps she has already taken with Old Mutual but the agent insisted the Nedbank cover would be terminated once the old Mutual contract was available. My wife asked him to call me and when he did I told him the same version. He repeated what he told my wife and I agreed he could go ahead. In late 2017 we went to Pretorius Branch of Nedbank in Pretoria to cede the Old Mutual contract. The branch called the housing division that we spoke to over the phone. The agent from housing told us that Nedbank no longer accepted policies from other companies as surety for homeloans. When we compared the two policies we realised Nedbank offered no Disability Cover and decided on the spot to cancel the Nedbank cover. The agent from housing division asked us to write a letter of cancellation which was followed by forms of releasing the cover from the bond account. To our surprise, we received an email from Nedbank requesting us to do the steps we did at their branch in January 2018. We resend the email with all the details requested. We never heard anything again from Nebank until they made another debit of R5 689.24 from our bond account on 02 June 2018 upfront. We lost faith in Nebank as a reliable institution to do business with and we have no alternative but to get legal advice as we are paying for two products which serve one purpose.