Samsung Mall of Africa

I took my phone for repairs on Wednesday, 8 May 2019 where I specifically asked to be contacted before any repairs could done. When I phoned the store on Saturday, 11 May 2019 the technician had not touched my phoned and read everything written on the job card and I asked him not to do any repairs on the phone before calling. I phoned the store again on Thursday, 16 May 2019 and asked to speak to the manager. He spoke with the technician and said I will be sent a quotation on the costs. The technician sent me a whatsapp on Friday, 1 May 2019 that repair completed and the costs are R1200 where I asked him of the quotation and he said I was rejection the quotation and he will remove the parts replaced to fix my phone. The chat was lenthgy and I told him I will call the store to speak to the manager. He sent me a whatsapp that he spoke to the manager and he or she approves of his decision. I phoned the store and explained to another manager what happened. Saturday 18 May 2019 I received a call for my email address which I gave her and the technician sent me a whatsapp for the correct email which I rep**** and the email stated the repairs will now be R5200 because there are missing parts.

How does a R1200 repair move to R5200? Why didn't he tell me about the missing parts? Is the store or technician being spiteful as I am insisting on a quotation? He claimed to have phoned me and he never did. What is really going on here?