Car Sale Documentation Issues

Summary

If you sold a car in Indiana and forgot to keep a photo of the signed title or fill out the bill of sale, you should report the sale to the BMV within 31 days. You can report the sale online through the Indiana BMVs website or in person at a local BMV branch. Ensure you have all the proof of the transaction, such as Facebook discussions, proof of money deposit, and any other relevant documents. Contact the Indiana BMV at 888-692-6841 for further assistance.

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Hello, I sold my car last week and it was my first time doing so I didn't fill up every papers like the bill of sale. 
After selling the car and removing my plate, I realized that I forgot to keep a photo of the signed title and also didn't fill the bill of sale out. 
As I was able to sell my car by facebook, I contacted the person to whom I sold my car to ask him to send me a photo of the signed title but so far the person seems not to want to send me that. 
I fill out the Affidavit form to let the BMV that I sold my car telling them the price and the buyer name. I got also the buyer address through peopelfinders, but I’m not sure it’s the good one. The BMV ask me also to send a email to tell her to register the car immediately. 
I’m very confused. What should I do at this point to avoid being in trouble if something happened? 
I have all the proof that I was able to collect: Facebook discussions, proof of the money deposit, her pictures, and the paper that I sent to the BMV.
What is your location? The rules for selling a car and the required documentation can vary by state.
Indianapolis
What date did you sell the car? In Indiana, you must report the sale of a vehicle to the BMV within 31 days.
July 1st
You're still within the *-day window to report the sale to the BMV. Please ensure you do so promptly. For further assistance, contact Indiana BMV at *-*-*.
How to report it
You can report the sale online through the Indiana BMV's website or in person at a local BMV branch. Here's the link to the online portal: https://www.in.gov/bmv/online-services/