If the coupon is expired,
the test-taker will be notified during the application of the coupon. They will not be able to add the coupon and must pay for the test on their own.
If the coupon has already been redeemed,
the test-taker will be notified during the application of the coupon. They will not be able to add the coupon and must pay for the test on their own.
If the test-taker attempts too many tests without receiving a result,
the coupon credit on their account will expire. In these cases, they should contact support for assistance.