Yes it does make a difference. You have to make sure to get the wires under the right terminals or you will have bad problems.
I am a bit confused though. OP, are you talking about something like this twist lock inlet box mounted on the outside wall of the RV?
Maybe something like this?
Or are you talking about the male end of the power cord that plugs into one of the above?
Either way, it's probably wired fine if everything is working right now. Might it be possible to pull one or the other apart (make sure power is off) and rotate 180°?
Or or, am I off base with what your issue is???