Terrible customer service

My bond installment was debited twice on the 30 september. I went into the branch this morning to rectify and was told to call the call centre on *** and go through to the Homeloan collections department. I left the branch and called on my way to work. I was put through, a guys answered who kept on saying he couldnt hear me and then he cut the call. I thought it was maybe because i was driving so didn't think much of it. I called again this afternoon, was put through to another guy who heard me quite well, took my details, verified everything and told me he will put me through to a specialist who will assist in reversing the additional debit. Once he put me through, the call cut after 5 minutes. So i called back, the reception lady could hear me, i asked to be put theough again to homeloans collections. When i got through, the guy on the other end could hear me and basically told me to hold on and put me through to someone else. The lady came on and i greeted her but she kept on saying she couldn't hear me and cut the call. How is that some people can hear a person and others can't. Needless to say, my query is not resolved. Nedbank, assist if you can because its ridiculous that your lines are so terrible.