Yep, I call BS. I just recently went through a HUGE misunderstanding with the bank we used (past) for our vehicle loan. They put 2 30 day lates back to back which dropped my dh's score 100 points.
I had called once and gotten a b*tch that was not only rude but told me it was impossible to change it. My husband went to the bank to talk to someone.........rude again......said no.
I called AGAIN.....got a very nice lady........and BEGGED. Told her the whole story (it was honestly a big misunderstanding.....but in their eyes....we were late). After jumping through a lot of hoops and begging........she took it to her manager and boom......within like a week the lates were gone. She even gave me a control number for reference......which is a number they are given by the CRA anytime a change is made on someone's CR.
It IS possible. Stay persistent. Call, write.....just keep after it. You
can find someone that will listen to you and change it.