Hello,
Sorry to say Your whole website is slow.
This is the result of google pagespeed insight before deactivating download manager and wpdm addons on mobile and desktop
This is the result after deactivating download manager and wpdm addons:
Also I have checked and haven’t found any php/js errors of wpdm. I have realized only WPDM is not the reason of the slowness. Please take other measures.
Thanks