Receiving error message when trying to upload to file manager

I posted about this issue a while ago, but I'm still not having any luck with any of the suggestions that were provided.

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I've uploaded the error message. This appears everytime I try to place a file in a folder or make a new folder. I am able to upload files to the file manager, but I can't sort them afterwards.

I've tried as a member, as an admin, on Google chrome, on Edge, after clearing cache and cookies, after reloading website from server.

Club: 6423, Civil Speakers
File name: (Everything not in a folder)
File size: Range 83 KB - 129 KB

Thanks!

I just put a bunch of your file in  "Executive Meeting Minutes - 2025"

Click on the reload link at the bottom of your site and try again.

No luck. Still the same error message popping up whenever I try to do anything with folders.

Oh wow, I've maybe figured it out. I tried using personal hotspot wifi from my phone instead of my wifi at work and now it seems to be working. Somehow my work wifi is giving me this error apparently?

I used chrome and it worked. 
Try clearing your cache and cookies for your site.

What EXACTLY are you putting in the folder box?