Pathetic Customer Service - Worst customer service ever experienced

I visited BMG Secunda branch on the 08/02/2018 - Last week Thursday in order to purchase a bearing for my cars air con unit after failing to purchase one in Standerton and when the measurments were taken the salesman - Tefo Lawrence Mafole advised that they have got stock of the bearing that I was looking for after I had explained my situation and the bearings measurements were recorded as 35BG5220 which I was charged for in an amount of R475.38 and I was given the wrong bearing as the measurements are 30BG5220 and payment was made via EFT into BMG's account and payment was confirmed as received and I only saw the error on the Friday 09/02/2018 when wanting to complete the repair and I called Mr Tefo Lawrence Mafole and advised of the error and was asked to provide an SOP No: on the invoice which is SOP:262020 Document Number: 0204/ ********** 6 and I was told by Mr Tefo Lawrence Mafole that he would rectify the error and contact me back which did not happen and I called again and was made out to be ******** when talking to him about the error and was told that an order has been placed for the correct bearing and that I would receive the item on Saturday 10/02/2018 and that I would be contacted with further info and to request my address and to arrange with the driver for the exchange and that did not happen either and i am still awaiting his call and it is now Monday 12/02/2018 at 10:11 and was asked if i am sure that the bearings measurements are actually correct as being 35BG5220 and was asked to commute to Secunda with the aircon unit and sample of the bearing which was already supp**** on Thursday 08/02/2018 wherrby Mr tefo Lawrence Mafole measured the bearing size before checking stock availability and when given the bearing Mr Tefo Lawrence Mafole failed to verify that the bearing I was supp**** with was in fact the correct bearing and size - which it is not and also Mr Tefo Lawrence Mafole was witnessed degrading upper management by making inappropriate comments and joking around while awaiting payment confirmation and now I as a client am seriously reconsidering doing business with BMG in the future as I now have my doubts and suspicions as to whether staff of BMG actually have the relevant product and system knowledge in which to perform their duties and I don't appreciate being made out to be ******** when making any form of purchase of any product even after the salesman himself took the measurements of the bearing as this shows a lack of knowledge and customer service.