Sim swap nightmare with Vodacom

I have been struggling to do sim swap with Vodacom since 31st October 2019, always speaking to different call center agents who doesn't have a clue how to help, I had the number for 18 years, had a contract with Vodacom for 10 years with the same number until I migrated to prepaid in 2017, suddenly my number has different id number it doesn't match with my details, no one seems to care or wants to help, I have a small business that I run with the number in all of my correspondence,ads and even my word of mouth referrals can't get hold of me, I'm beyond angry with Vodacom I don't even know how to explain it. I need legal help please, what must I do to get my number back