Bad service received

My name is Jeanette Chauke, I settled my Nedbank account with Vertex on the ,12th Nov 2018 asy name has a default on itc which I was promised it will be cleared within 21 days by vertex and that I will receive paid up letter within 3 days till today no clearance no paid up letter...I spoke to an agent at Vertex by the name of William who spike to different ppl even their legal department about me getting paid up letter but to no avail, Vertex is telling that Nedbank need to send the paid up letter .I also spoke to Nedbank consultant he told be that Vertex is the one responsible till today the 29,th Dec ni paid up letter received.why must we settle our debts if we can't get proof that we have paid I don't think both vertex NIR Nedbank wants to take responsibility but so quick to collect from us this is totally unacceptable Idont see making business with Nedbank again.