If you’ve used your debit or credit card at Target between November 27 and December 15, read this article. The most important takeaway:

Debit card holders: call your bank immediately. Debit card users should be especially vigilant. Credit card users won’t be out of pocket if they suffer fraud and contest the charges, but the opposite is true for debit card holders since fraudulent transactions may take their bank balance to zero.

Accordingly, Velasquez recommended that any debit card users who might have been Target breach victims immediately contact their card issuers and ask for advice. “Tell them you’re a victim of the Target breach,” she said. To help combat fraud, different institutions offer different options, such as putting passwords on accounts or changing PIN codes. “But alerting your specific financial institution is really the way to go, because they all have different rules,” she said.