I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear that this happened.
If the dealership gave you all of the paperwork at the time you bought the car, and the paperwork you signed match the loan that you have, then all of this is legal (and it would be considered a car loan if your car is securing it), even if it's not with Ally Financial Auto.
The Better Business Bureau looks into consumer disputes, but participation by the companies is voluntary, so they may not respond. You can file a complaint at www.bbb.org. I mention that not to discourage you, but because you may also want to ask the Maryland Attorney General to look into the situation. They can investigate, and if necessary fine the company or take other action to ensure that this type of thing never happens to anyone else.
After you do that, read all your paperwork for the car and compare everything you got from the dealer with what's on your loan. If they gave you a higher interest rate than what you agreed to pay, you may be able to sue for any extra amounts you paid.
If you have any questions or concerns about what I've written, please reply so that I may address them. If I did not address the specific thing that you wanted to know, it may not have come across clearly to me, so please restate that question. It's important to me that you are 100% satisfied with the service I provide. Otherwise, please rate my service positively so that I get credit for answering your question. Thank you.