New Vodacom contract migrating a MTN existing number

I took out a new contract with Vodacom in December through my Vodacom app, advising Vodacom not to activate the number/account as I want to keep my old MTN number which only expired in January. After cancelling my MTN contract and going onto pay-as-you-go I phoned the Vodacom call centre 082111 to migrate my number. I was sent from pillar to post without a resolution. On Saturday I went to the Baywest Mall Vodacom branch where the sales consultant advised she cannot assist me, we have to speak to the call centre. She phoned the call centre in store to do the migration, but she was also sent from pillar to post. After trying for more than a hour she gave up and advised as per the call centre to try the call after sales again on ********** . On 22 Jan, I phoned ********** and 082111 again and was told to phone 082114, they transferred me to the solutions department. They gave me instructions to port my MTN pay-as-you-go number to a Vodacom pay-as-you-go number, which I did. I have now been struggling this whole week to do the SIM swop from the Vodacom pay-as-you-go number to the new Vodacom contract using my old MTN number. When you phone the call centre they just keep telling you the number is not yet showing without giving a solution to get the SIM swop done. This number is used for business purposes and we cannot afford for the number to be unavailable for this time period. This makes me regret moving from MTN to Vodacom. Surely keeping your existing number should not be such an issue.