From your image it looks like the ribbon is lying on the XZ plane, and elongated along the X axis. If so, I think you just need to adjust the bend deformer's H rotation parameter. If the ribbon is oriented differently, try adjusting one of the other HPB parameters until you find the right one.
In fact, in your current setup it looks like you have already adjusted the proper parameter for the left bend deformer, so adjust the same one, probably in the opposite direction, for the right bend deformer. Hope this helps.