[ARCHIVED] Application of a voucher codes does not zero the cost of a course - confusing

[angusmc]

We are running a course that the students either pay for when they register, or they use a voucher code to take the course free of charge.  We sell the voucher codes in bulk to companies that use course, but anyone can take the course if they are willing to pay.  Why when the voucher code is applied does the cost for course not "zero out"?  What happens is there is no evident change at all in cost, and many students get confused and back out, rather than try to proceed with the course.  This results in a lot of calls to our trouble desk, and also calls to the company that provided the voucher.  Can you please fix this?  It would seem like an easy and reasonable fix that if the voucher code is valid the cost should update to zero.