How to achieve a yellow cross on Rubik's cube from three yellow edges on the top layer?

I have finished the first and middle layers on a Rubik's cube and now I would like to complete the yellow cross on the third layer. Every instructions manual I have seen assures that there are one of two possibilities: either no yellow edges on the top layer (only yellow dot in the middle) or two yellow edges on the top layer (it is a line or an "L" shape). However my Rubik's cube has three yellow edges on the top layer.

Firstly I thought that it is possible to apply the common algorithm: F U R U' R' F', but this gave me no result.

I also tried to switch the edges (I thought that this may reduce the number of yellow edges). The result was either three yellow edges or one yellow edge. Both cases doesn't occur in any instructions.

• Did your cube pop once by any chance and was put back together incorrectly? Or someone pranked you by flipping an edge? Having a single rotated edge is indeed not possible on a regular 3x3x3 Cube, which is why you are unable to find any algorithms for it in tutorials. Aug 21, 2021 at 17:14