Lexus Financial Services accidentally logs a "refund" into my account and then attempts to collect on it

Since 2000, I have been nothing but a passionate Lexus owner and advocate. Between my wife and I, we have purchased or leased a total of 4 Lexus vehicles (IS300, 2 RX350s and an ES350). While my experience has been fairly positive that all changed last night when I received a call from LFS collections department.

I get a call and am immediately put on the defensive due to the agents aggressive nature and demeanor. I am told I am behind in my payments and that I owe ~$1300 to LFS immediately. Moments before, I'm enjoying Mother's Day evening with my wife and now I'm scrambling to figure out what went wrong with an account that has been paid diligently through auto-pay that I set up on the LFS site about a year ago.

Digging a bit deeper and asking a number of questions the agent finally acknowledges that something is amiss. I am put briefly on hold only to be told that I managed to obtain a refund and withdraw ~$838 from my account on May 7 and that I need to pay that back. I ask for key pieces of information such as who made the request, which account received the credit and how I can even take money out of this account but she is unable to give me any information other than the fact that I must have done it. After about 40min of this utter nonsense she agrees that further information is needed from LFS customer service and that I should call the next morning. She also tells me to check with my bank.

After a pretty sleepless Sunday evening, I check with my bank in the morning and see that there's no pending credit of any sort. I call LFS customer service in the morning and I get greeted by a somewhat agitated agent that asks me to confirm all my contact information before saying anything (the same information that I had updated the night before). Once again, I'm put in the position of defending myself since once again the call starts with me being told that I am 45 days delinquent on my account and that it is past due. I’m placed on hold and when she returns a few minutes later,

I am told that there has been an inadvertent credit that has been placed on my account by accident but I still owe the amount that is due! I tell her that there is some mistake and that I refuse to pay the amount until she checks my history. We are both annoyed by now (I am annoyed that I have to pay an amount I don’t owe and she is annoyed that I’m not just willing to accept responsibility and pay) and she once again places me on hold. She comes back 5 minutes later and tells me to wait for my account to update at 11pm CST and to call back tomorrow. 

So here I am waiting for my name and account to be cleared of any wrong doing. I am still fuming since last night and so I’ve decided to write about my frustrations with the company. I’ve yet to receive a single apology of any sort and I’ve wasted hours of my time to prove my innocence.