Please help Impossible to Add photo in portfolio

Hello everyone
I have my website running for at least 5 months know and everything worked perfectly until Tuesday.
When I create a new portolio everything works just fine, sections, texts, details etc…..
But when I click on the button “+ add media” a window open with all my photos, then I can upload and select the photos I want in my portfolio.
Once the selection is done I clic on the button “select” down right of the window and the window closed but the photos I selected isn’t showing and nothing happen !!
So impossible to add photos in my portolio why?
What can I do please ?
I am a photographers and the theme of the website is Oshine from theme forest
Thank you all