... and you think dropping a check off in person will help?
My (previous) mortgage company deposited my mortgage check... and I have no idea whose account got credited for it, but it wasn't mine.
The check cleared, I marked it as such in my bank book, and the only clue something was wrong was when I went from 0 bill collector calls (since I pay all my bills on time) to 4 in one day all about my mortgage. Even after I opened a case, and they started investigating, AND finally credited me back, they STILL had the hounds calling me.
I had to tell them the next call was going to my attorney before they stopped.
So, even dropping that check off in person won't necessarily help. Mistakes can (and do) happen.