Under the federal Fair Debt Collection Practices Act, third-party collectors cannot threaten you, call at all hours (generally before 8am or after 9pm), call you at work after you tell them to stop, or lie about what you owe.

You can demand they “validate” the debt in writing within the first weeks of contact — and you can send a written request that they stop contacting you altogether. Keep copies of everything.

Be careful before paying or even acknowledging an old debt: in some states, a payment can restart the clock on how long they can sue you. When in doubt on an old debt, get the details in writing first.

This is general legal information, not legal advice, and reading it does not create an attorney-client relationship. Laws vary by state. For your specific situation, talk to a licensed attorney in your state.