I didn't want to take a hit on my credit score for late payment
.. bank also said that I'm still responsible for the loan even though I traded in the car.
I understand that, but a credit hit for late payment doesnt happen until you are "30 days late" . If your original payment date was june 11th, the same day you traded in your vehicle, it would have showed late in the banks system as of that date, but the hit to your credit would not have been until July 11th for being 30 days late.
Saying that, it sounds like I am piling on, which I am not attempting to do. All car dealers normally take a bit of time to pay off a loan, some more than others. The issue you will likely have is, tesla pulled the loan payoff as of whatever day you traded in your vehicle, and gave you whatever credit toward your new loan (if any) based on that value.
You made an additional payment, but unless your and tesla's payment literally "crossed in the mail", you may have a rough time getting that payment back. Tesla will pay whatever is owed on the vehicle when they go to pay it off, and that amount is going to be reduced some by your payment. If you dont care about getting that back, then its likely it would be paid off before you get 30 days late before your next payment is due.
If you want that money back, you may have to jump through some hoops trying to prove when you made the payment, etc.
The answer to your original question is, "sometimes I have read that tesla is slow with payoffs, especially around the end of the quarter".