Upset - why MTN?

I started a data contract with MTN through my Mr Price Account this year. I made a late payment on my Mr Price account, which resulted in me not getting my data, which comes on the 12th of each month.

I then contacted the Mr Price call Centre who told me that I am supposed to get my data for the month even though I didn't make the payment on time. They said that they would contact MTN to do an enquiry, which I appreciated so much.

Later during the day. They called me again, and said they've contacted MTN, who told them that my cellphone number is on prepaid so they aren't able to assist. How? I don't understand.

When I contacted Mr Price previously about possibly canceling my data contract, they told me that once I cancel the data contract, MTN will deactivate my number. I'm very confused, because how can you do that, but you're not able to pick up that I have a data contract? C'mon now!

I've been a loyal customer for years to MTN and I've made payments on time. I just missed 1 payment. Please assist.