why when we have linear polarization its said that there is no angle between orthogonal components which gives us infinite axial ratio
but its not true because there could be linear polarization with 45 degrees between the X component of electric field and Y component of electric field.
?

Axial ratio is a characteristic of E-vector's elliptic orbit, which is always taken with respect to polarization plane (ellipse main axis). The 45 deg may be just a relative angle in some outer coordinates. The impossible thing of non-orthogonal basis (Ex^Ey=45deg) you are talking about can be found only in some specific planar projections, which does not make sense. Well, in near field you can find some weird distortions between E and H, but H is not E.

thanks alot