F1 university transfer dilemma

[Okie101]

I started in a MBA program last January at university A. During the first semester I applied for a better program at university B and got accepted. The problem is that I still owe money at university A, 2100$ to be exact, I talked to the international student advisor at university A and I was given a paper to be signed by the student account office saying that we made payment arrangements, student accounts would not sign it unless I paid at least 1500. The problem is that my sponsor has been delaying the payment due to trouble back home. University B starts next month and I still havent transferred. My question is, can university A deny me transfer because of money, and how much time do I have before it's too late to transfer

Any answer would be appriciated