How to use mtn Bizplus point for airtime or data

I borrowed #7500 worth of airtime from MTN yesterday and I paid back today but the borrowed airtime is not in my account. And while I tried to buy data plan with it yesterday...

i can't use my mtn buffet plan, the youtube not working and then expires...

I subscribed for my smart data 10,000 for 53gig this morning and I can't use it why what happen mtn give solution to it...