We are sorry to hear you are having trouble with the registration payment.
We would suggest trying another card, double-checking that your billing address matches exactly, and contacting your credit card provider to make sure they aren't blocking the transaction.
In addition, SLAS has a payment processor - Cybersource - that has a higher level of security and can actually decline a transaction even after the payor's bank has approved it.
In these instances, you will show that your credit card was authorized by your bank but no payment was made because the payment was halted on our end. You need to call your credit card company and make sure they have the correct address for you. We have seen this with multiple attendees and the address was the issue. Once you update the address, please try again.