what does this mean?

“Regrettably the Help and Quality Teams are unable to offer a critique or feedback on your rejected submission.”

This is not a serious response.
Every design that I submit is a serious job for me, and I put all my effort into it.

I’m really upset, because I have no idea WHY I was rejected.

What should I do to avoid making the same mistakes?
“Regrettably the Help and Quality Teams are unable to offer a critique or feedback on your rejected submission.”

Cricket sound here.