JUST A SMALL REQUEST

I have had my cell phone contract forever I always had quick sim somewhere along the line quick sim was cancelled by who and on whose request I DO NOT know. however I recently visit Vodacoms Boulders store to change my sim to a micro sim and was told that I don't have quick sim. so the consultant tried to enquire about this. to my disappointment he was unable to assist me. then I receive an SMS to rate the service so naturally I rate it as bad. someone calls me says they will look into it and then I get a SMS saying quick sim was deactivated. seriously I need to find out who cancelled my Quick SIM and I need a ,micro SIM FOR my IPhone 5s that is all. someone who can make this happen please help me call me