Haven't written about it, but maybe I will one day. It was when I refinanced into my 15 year loan, I had to pay taxes at closing. OK, not a problem, but then the mortgage company paid the taxes AGAIN, sending my escrow negative. It would have made my payments go up by hundreds of dollars. Simple mistake - you just contact the town and they refund the money, right? Nope. The company kept telling me it might take SIX MONTHS to get the tax payment back. Constant calls, transfers, people who had no idea what I was talking about. Escalated calls open with the company, and no responses. Several weeks went by and they hadn't even contacted the town! So I took matters into my own hands, went to the lawyer who did the closing to get them to get the refund instead, and had the check in my hands days later.
Joke was on the mortgage company though - I reported them to the CFPB, and kept the check in a savings account because I knew they'd re-run escrow one day. It took them a year to re-run it, and sure enough, my payment went up for a year. But I made sure they got that money as slowly as possible, after the experience I had.
I haven't had problems with them since then, although I still can't stand them because of what happened and how they treated the situation. But I can't refinance away from them because there's no way (1) I can beat the 2.75% rate and (2) I'm not letting them cost me money by refinancing. So I'm stuck with them until either they decide to sell my loan or until I pay it off.