Contract number swap

Good day, did an upgrade through retention November and told the lady I want a similar contract from what I have currently as I use data share and if I don't upgrade you will charge me more, but my data didn't last it was only 16days that I would use up 200gb so I opted for contract number swap, I was told the contract number will be prepaid but now they deleted the number all together I want that number back as prepaid as my banking app is linked my everything is linked on that number.