It’s difficult to give advice without seeing the environment in question.
It could be the lighting or occlusions in your setup, or the contrast or gain.
In your first screenshots for instance it seems to have difficulties stereomatching the shelf area that is mostly black.
A workaround could be to use a ROI mask, excluding the uncertain areas.
Please send us an SVO to support@stereolabs.com referencing this post, replicating this setup, it will be way easier to investigate on our side.