I had to have some charges reversed and I had no issues.
It was a really odd situation, too. I was coming back from San Diego to central valley, and I learned that the day I got back, withdrawals had been made from my account from an ATM in orange county. 3 different withdrawals totaling like 1200 bucks. I talked to my bank agent and she said they needed both the card and my PIN number to make the withdrawal, but I had my card with me the whole time. Really weird but the charges got reversed without any problems.