The same thing happened to me
Unfortunately your submission isn’t ready for ThemeForest and cannot be resubmitted as it did not meet our minimum requirements for quality and/or marketplace policies. In order for submissions to be considered for sale they must be of high aesthetic and technical quality.
I don’t understand. I have seen “not so good designs” getting approved and mine was rejected (Which I think was better than some other approved designs) and they did not give me a reason why they rejected the item.