Agreed with @Wristy. Also, some other questions:
1. What is the source of your information?
2. Would you like to confront the employee about this and ask what happened?
3. Were they just charges or were they proven?
(Just as an example, using a company credit card for personal expenses is 'financial misconduct'. But sometimes, it can be accidental, misinterpretation, or just due to circumstances like your own card being blocked)