********** upgrade resulted to a massive amount debited from my account

I am frustrated, the was a ********** upgraded an I ended up owning R3000+ as oppose to a R300 that I pay monthly. I told Smangele Ndlovu that I do not have that kind of money then she put me through to accounts spoke to Zolile and he confirmed that the that the debit order has been stopped and that was the 18th. On the 20th the debit order went through and all my debit order were returned due to insufficient funds. I need my money returned. I am tired of this matter. Also can my business relationship with Vodacom end.