They’re the worst of the absolute worst: scams that target people who have already lost money to a scam. If you or someone you know paid a scammer, here’s what to know to avoid scammers who pretend to be helpers.

One of the best ways to fight fraud is to talk about it. When you know scammers’ tactics, they’re easier to spot and avoid. The FTC has some facts about fraud to help you start the conversation.

Scammers know that applying for veterans benefits is at the top of the to-do list when you’re getting ready to leave the military. That’s why they pretend to be with the Department of Veterans Affairs (VA) and offer to help you apply for benefits if you pay them — even though it’s free to apply with the VA. So if you’re applying for veterans benefits, get the help you need while avoiding scams. Here’s how.

Let’s say someone contacts you unexpectedly and says you have to pay to fix a problem, get a prize, or something else. But then they say the only way to pay is by bank transfer, wire transfer, cryptocurrency, payment app, or gift card. Well, reports to the FTC show that’s a scam.