Paying for services I'm not receiving

I had a contract with vodacom and I decided to cancel it but one of the sales lady convinced me to take a new phone. I explained to her that I have lost the number and this is the other reason for cancelling. Her respond was she is going to send me a new sim card with old numbers so I can continue with the contract .I took it but now I'm struggling the sim is not active I went to the branch I was told to pay for sim swap I don't understand why should I pay can I get working sim because now I'm paying for services that I'm not receiving my vodanumber ***