Hello ladies

So back in October, I was scheduled for my NT scan. They scheduled me based on my LMP and not on the date of ovulation, so I expressed to them on the phone during scheduling that I thought this was too early and that I thought I should come in a week or two later just to be safe. They reassured me that they account for that kind of thing when scheduling and so everything would be fine. Well, of course when I got the NT scan done, it was indeed too early. At first I didn't mind, because it meant that I would get to see my baby twice! But now I'm getting the bill for both, and when I discussed the issue with billing, they basically told me that there is nothing I can do to dispute it because I came in and had the test done both times, therefore they have to charge me for both.
What would you guys do in this situation? I was assured that it would not be too early for the test and then was told that it was too early and would have to come back, so I don't see how that could possibly be my fault! Also, they sent the first bill to my mom's address (I guess they had it on file from long ago when I went to that hospital as a kid) and the second bill they didn't send anywhere! I was alerted about the second bill by my online web portal, but the first one is nowhere to be seen, except for the paper bill that my mom got! What the heck is going on here!?
This whole thing has got me feelin like this:
Re: What do I do?!
Also, dealing with medical billing stuff is a huge PITA. I hear you on that one. I despise it with a passion. No one ever has an answer, ever. And then they take almost a year to charge you for stuff...after you think you're all paid off. Ridiculous.
Married: 1/2008 ~ DD#1: 3/2012
TTC #2: Started 4/2014 BFP 7/30/15 MC 8/3/15 BFP 9/4/2015 EDD 5/16/2016