Overpay is like I have a Turmac petpet in trades. It's worth 3m but someone just offered like a Chokato (TCG) which is worth 12m. It's a duped item and their trying to get rid of it.
Especially if it is a Chokato (TCG). Even if you innocently get a duped item on your account you will most likely get frozen.
This is like morning old news. If anything happened (like TNT removed all duped items. Did they remove any yet?) since 18 hours ago please update us!