Vodacom poor service

In 2021 I moved over to Vodacom. I was originally with MTN and I was told that I could keep my existing number while Vodacom would port my number on their network and everything would be fine. Initially I had no issues but then this year I have had endless problems with my number being reused by MTN. So now my number is being given to MTN customers. This has now happened 3 times in the past 6 months where suddenly when people call me then the calls get routed to someone else who also has my number. I have pleaded with MTN but they are unhelpful as I am no longer their client and they say I should speak to Vodacom. Then Vodacom just keeps saying the issue is resolved but it keeps happening again and again. The sales guy at Vodacom doesn't know what to tell me because he says he's never had a case like this.

So now I'm sitting paying for a contract linked to a number that I cannot use because its not secure, I worry about what could happen if my OTP's are sent to someone else, and seems no one will help me but I have to pay for the contract.

Very unfair, very unhelpful, very poor service. Do Not use Vodacom