What is the reason for giving hard reject our WordPress theme ?

We can’t make out what’s happening to our themes. Each and every WordPress themes are getting rejected.
Messages indicate that the problems are with our designs. They used to say that either the items carry less content or they are not qualified enough to compete in Themeforest.
But, Themeforest is approving the HTML & Shopify versions of those rejected items without any complain.
We have been puzzled to find it out where our problem is.
We use free page builder to develop the themes. Is it a problem that can be the reason of rejection?
Note: We use Elementor page builder.