CINEMA SCOPE & PROXYS & ASPECT RATIO

Hello,

I shot a Musicvideo on ARRI ALEXA MINI with Anamorphic Lenses (Cinema Scope), now I try to make Proxys from the Material, but there is no Option with the right Aspect Ratio?

I did shot the first time with these lenses...so I think I just miss something out?

THX for any Help