Disorganized And Unhelpful

I don't do all of my banking with LMCU, just my auto loan, which I acquired 5 months ago. I have had nothing but trouble with LMCU since then, unfortunately. About 3 months into my loan, LMCU suddenly mailed me a document stating they were charging a $300+ fee to my loan due to insufficient insurance. My insurance was exactly up to their code and they had been given the proper information from day one, as proven by my insurance provider, but they claimed to never receive it (odd that they'd wait a whole 3 months to pursue that if it WERE truly the case, though!). Once this had been sorted out, I requested proof that this was resolved, which LMCU did promptly mail me. However, about a month later, I received yet another notice, once again suggesting that I had insufficient insurance, even though it had now been provided to them twice. After much wasted time and a lot of frustration, I was assured this was resolved again and so far (a month later) I have not gotten any more notices about that. I did, however, just receive a late payment notice today for a payment that I had made well before the due date, but which LMCU claims not to have gotten until 16 days later. Despite having my bank's statement to prove the payment was on time, they refused to work with me on this and would not remove the late fee, saying there is no way to override or waive it at this point (which is completely untrue) and either I would have to pay the fee myself, or have my primary banking institution pay the fee for me, since LMCU claims it was the fault of my bank, not LMCU. I've banked with my bank (Huntington) for a decade and have never once had a problem with my bill pay and considering my only experiences with LMCU so far consists of them repeatedly losing pertinent information on my account, I know that this is an error on the part of LMCU, and not my mistake, nor my bank's mistake (Huntington). I am now contacting an attorney, because I refuse to let their lack of professionalism ruin my great credit history. I would never recommend LMCU to anyone.