The risk of financial institutions that Sam is a victim of is Identify theft.
Financial institutions, while offering numerous conveniences and benefits, also expose customers to various risks, one of which is the unauthorized use of their financial information or identity for fraudulent purposes. In Sam's case, his bank card details were likely compromised and then used to make unauthorized purchases.
This can happen through various means, such as card skimming devices, data breaches at companies where he might have used his card, or even through phishing attacks where he might have unknowingly provided his card details.