What is your proof? Did you have someone with you? If you have proof and the rental agency is lying and trying to collect a fee not owed, they may have to:
1- Stop asking for the money;
2- Pay you a statutory penalty;
3- Pay your attorneys.
If you have the proof and all docs, a consumer protection office like mine would evaluate at no charge.
Dispute the charges if applied to your credit card and/or contest the pleadings if they begin a cause of action. Sounds like you have a somewhat convincing argument if you have a witness or some other evidence of your drop off. Good luck.
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