Unable to Upload Avatars

Hi.

I have been using this plugin for years without a problem on my forum.
Recently someone tried to change their avatar but was unable and they got an error message.

I have attached a screen shot of how and where people try to upload images:

https://www.thewargameswebsite.com/wp-content/uploads/2026/08/av1.jpg


And one of the error.

https://www.thewargameswebsite.com/wp-content/uploads/2026/08/av2.jpg

Any ideas what may be causing this?

The page I need help with: [log in to see the link]