The credit card verification we use is pretty strict. Since November 2015, we’ve never had a chargeback or fraudulent transaction. Your billing address has to exactly match what your credit card company has on file. If in doubt, pull up your card statement and see where they think you live.
If it fails to verify you might still see an “authorize” transaction on your card. This is from Stripe (our processor) saying:
“Hey, does this person have enough money to cover the charge? Cool, here is their address, does it match what you have? No? OK, never mind.”
If it does match then it does what’s termed a “capture” transaction. This is where they charge your card for realsies.
So the good news is: you aren’t charged for the auth transactions, but they do temporarily count towards your credit limit. After a few days, depending on the bank, the pending charges will drop from your account. If you need it, you can sometimes call the bank and get them to release an auth transaction early.