Featured image wordpress not showing front end

my featured image of wordpress are not showing in the front end though image are uploaded in media library .

can any1 help.

When i upload new image & set it as featured image it works but old images doesnt worked

Also my old files in upload folder are not showing me in media library

Hi there, Try uploading the images once again and see if that works or not. Thank you.

My featured images are not showing in the front end https://share-ask.com/category/quotes/ though they are visible in the backend