Fed up with Vodacom

6 Months ongoing struggle with vodacom. 6 store visits and 100 's of calls to the call centre with no record and different story's from every person taking my calls. all my calls come through as missed calls, no issue with my settings my phone goes directly on voicemail. Did a sim swop yesterday because according to the vodacom consultant that was the issue, my sim is old. That was not the issue, my phone still goes onto voicemail. It doesnt help vodacom calls me because they also reach my voicemail.