how to reschedule mcse exam

Hi all,

I purchased mcse exam vouchers and its expiry is tomorrow. Due to some personal reasons I am not able to give the exam. How can I reschedule my exam. I have not registered sofar. I just purchase and kept. I need to prepare some more and give the exam. If I couldn’t I will lose my money. Please help me with some good suggestions without wasting the vouchers. Thanks in advance.

-raju