multiple beams in microstrip array

I have a 5x5 microstrip U-slot patch array in which I oriented the patches in a diamond shape (45° rotation around z-axis). I started seeing 3 beams in one plane. If I don't rotate the patches, I only see one beam. Could someone explain why I am observing the multiple beams with the 45° rotation?

Also, is seeing multiple beams have any relationship to dual polarization?

Thanks.