We do not issue refunds for registrations.
There are no exceptions.

If registering online, it is clearly stated and also explicitly written that we do not refund multiple "accidental" payments. (Screen shot.)

If the event offers a discount code or other method of discount, you must use it at the time of registration.
We do not refund the difference for any type of discount that goes unapplied when you register.

The amount you will pay is clearly indicated before your payment is processed;
if it is not the amount you believe it should be, do not pay.