Removing old number

Hi, I need help removing a very old number from my account.

The numbers contract in question ended and cancelled back in October / November 2020. The number still appeared in the Vodacom app, but I was told that it would eventually disappear on its own. I haven't paid for this contract since the cancellation date, as in it doesn't appear on my invoices.

Now in the last six months or so, I've been spammed by Elite Mobile to upgrade this number even though it was cancelled years ago (which is another issue in iteself? Why is Vodacom giving away my details to randoms?). And then Vodacom themselves started contacting me regarding upgrades for it.

I have spoken at least three times with Vodacom recently to get this number removed. They all said that they will come back to me, but nothing.

Please can someone just get rid of this number from my account? I don't understand why there is a problem?