To use my credit for next year's registration

I am really worried about how my situation is or has been handled, I'm a bursary student, fully paid, and obviously there are funds still left under my name, however I got emails that I have a outstanding amount that i need to pay I don't know how.

I app**** with the hop that I'd used the money that is left for my next year's first semester as my bursary delays to pay tuition fee, I'm told I don't have anything left, I've sent emails, tried calling but no luck, from there the line is always engaged