I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear that this happened.
If you haven't already, you may want to get documentation from the car loan company to see if any payment was made in case there was an error in the amount or something. There's a different plan of attack if they underpaid or if the check was processed for the wrong amount than if they simply didn't do it.
Then, you have a few options. One is to make the past due payment to protect your credit, then sue the dealership for any fees, extra interest, or other costs associated with their mistake. Another option is to drive to the dealership and stay there until someone will talk to you about what happened and how to fix it. Or you could have a local attorney send them a demand letter, insisting that they pay the amount due immediately and take steps to repair your credit in order to avoid a lawsuit. You could also go ahead and file a breach of contract lawsuit, but be aware that if you do that, the collection company will keep calling until they get paid. Also, you have to sue in the county where the dealership is located, so it could help to try to work things out first.
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