"Unable to make a miter flange" warning

I keep getting this warning and can't figure out why this bend isn't allowed. It should be a simple enough bend. Below are two pics that show what I'm trying to do and of the result. Now, for where my sketch line is for the sketched bend, I put it where it was right up against the other bends and I put it .001 away from them so there'd be no interference. No luck either way. Also, while explaining this, if you can throw in exactly what a miter flange is that'd be great. What it sounds like to me is it has something to do with the bending part of a brake press... Can't make something bend 180 deg with a press. Any help is much appreciated.

SolidworksParts And Features