are you using any gallery/media plugins?
try developer tools (or the likes depending on browser) to see if any errors appear.
Can’t help you much since it’s on the backend
can you look into the dev tools and see if there is any errors in the console?
@orangeworx @hyperionstudios guys, what is developer tools?)
I am a total noob)
hi dev tools is something you access via your browser, if you are using chrome you can right click on the page and click on inspect element, then you will be presented with a new section, there you will find console, click on that and find anything with a red line and read that to us if there is any.
Media sometime breaks if you have installed new plugins that may deal with galleries or sliders, have you installed new plugin on your website?
Can you remember what is the last change you have done before the media breaks?
I will suggest doing the following
Disable plugins one by one and each time you disable one test to see if the media back normal
If that did not work then you will need to post us your functions.php code of the theme you are using to see if anything not normal.
Also are you using a child theme? and what theme you are using?