Hello Everyone, I had applied to IOWA state and today got and email saying this:- "Our review

Hello Everyone,
I had applied to IOWA state and today got and email saying this:-
"Our review indicates that you do not have the prerequisite degree requirements for consideration for graduate study. Iowa State University does not consider your credentials as comparable to a US bachelor’s degree.
Thank you for your interest in Iowa State University. "
I did my diploma and then went on to my bachelors. Could anyone know what needs to be done here. This is not even a valid reason for rejection.
Thanks & Regards,
Chinmay Swami