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I'm sorry to hear about your situation. Yes, you would still need to pay. The only time that you could keep the item without having to pay would be if the statute of limitations had been exceeded, and that's multiple years, so they can still make you pay. Even though this was clearly their mistake, it's unfortunately not something that you get to take advantage of.
I know this is probably not what you wanted to hear, but it is the law. I hope that clears things up anyway. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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Thank you, ***** ***** luck to you!