Try a couple things.
1) This "should" have an annotation as part of the family. If not, if the letter is symbolic, it could be your problem. Symbolic lines won't orientate properly.
2) If it is indeed an annotation as part of the family, open the family and make sure the text or lable has "Keep Readable" checked in the properties.
3) Make sure it's hosted properly. If the element isn't hosting to the correct hosting element, it CAN do some weird things. So, I would guess in this case it should be hosted to a basic wall.
HTH,
~BMC