Alexander's star single piece flipped

[Mazzel42]

I recently found a 1982 Alexander's star puzzle. I solved it up to the point that a single piece is flipped. According to my findings this should be an impossible configuration. Before I try to take it apart and risk breaking a piece, I just want to be sure that I am not missing something and I just have to rearrange the colors or something different. So my question is: Is it indeed impossible to have a single piece flipped in a Alexander's star puzzle?