nedbank failed to assist me

nedbank call center has the worst customer services ..called in to query with regarding to the deduction that was made on my account call ref number : ***.....i requested to speak to the supervisor ..he/she never attended my call ..i called in several times with the same query and i never got assisted ...they were sending me pillar to post ...which is uncalled for ....as i have lost more airtime trying to resolve something that they did wrong they even gave me call ref numbers : and still didn't get any assistance