Most banks have fraud alerts set in place. That is, when there is unusual activity in your account, many banks will contact you to make sure that it is you, the card holder, that initiated the activity.
I recently received a text from Chase informing me that someone tried to charge 0$ ($0 and $1 charges are dead giveaways in that someone is testing the account to see if they could put a bigger charge through the next time) at a computer store. They asked me to text back either YES-it was me, or NO-it was not me. I texted back NO. Chase canceled both mine and Rob’s Sapphire cards and we await our new ones. Thank you Chase for contacting me and staying on top of things.