Product: Vehicle loan or lease

This loan was taken out on XX/XX/XXXX through XXXX XXXX XXXX in XXXX TN and financed by them through Bank of the West in XXXX XXXX CA. The first installment was due XX/XX/XXXX once monthly for 72 months. 
The Retail Installment Sale Contract states that there is no prepayment penalty is paid off early - all amounts due up to the date of the payment is due. 
On XX/XX/XXXX, the balance showed on the loan was {$910.00} and that amount was submitted electronically from my bank on the Bank of the West payment app and accepted. 
On XX/XX/XXXX, I logged onto the Bank of the West payment app to see if there was an update on when I would receive the title for my vehicle. It showed that I owed another {$50.00} - even though the balance was paid down to {$0.00} on XX/XX/XXXX - so I paid that electronically on the app as well thinking it was a service charge to obtain my title. 
I logged onto the app weekly to check on the status of my title and received no other updates. 
When I logged on XX/XX/XXXX, it showed that I had another {$2.00} charge, so I paid it electronically right then in expectation of receiving my title back. 
On XX/XX/XXXX, I logged on yet again and saw another {$50.00} charge and paid it thinking this was the last service charge. 
On XX/XX/XXXX, the app showed that I owed {$0.00} and thinking that that was holding up my title, I also paid it. 
Today, XX/XX/XXXX, I received a phone call from Bank of the West stating that my vehicle loan account was delinquent and that I owed a little over {$500.00} and that payment was due today immediately to avoid repossession. 
When I questioned what this was for and requested to speak to a supervisor, the collector hung up on me. 
I called the Bank of the West back and spoke to a supervisor XXXX who was also communicating with his supervisor XXXX - that XXXX transferred me to. 
They stated that this amount resulted from a {$60.00} payment that was due in XXXX and the rest of {$500.00} amount was late charges on this payment. No one was able to explain to me why I owed the {$60.00} - or the other two {$50.00} payments I already made. All of these three people also confirmed that due to a glitch in their system, no one was notified of the payment due - not the app, not them, and not me. The glitch even prevented them from mailing me a letter about it. This was all on a recorded line at the company and I can provide the times of these calls today. 
All that XXXX would tell me is that it was owed- even though they don't know why and can not provide documentation of why - and if it is not paid they will reposses my vehicle. 
In my contract at financing, it states that a late charge would be assessed if payment is not received within 10 days of payment being due. The late charge is {$1.00} or 5 % of the part of the payment that is late, whichever is greater. 
Now, I do not understand how I can be late on a loan that has no balance- I can provide a screenshot of their app showing no balance owed- but even if it was late, how does the late charge equal over {$500.00}? 
The fact that they are not providing with proof of a payment due, they are charging more fees after the balance was paid off, they are trying to collect a " debt '' that they themselves admit was never disclosed to anyone that was due ( including late charges on this " debt '' ), and they are threatening me with repossession, I believe this falls under an abusive collection practice under the Frank-Dodd ACT and is a UDAAP violation.