Hello, it's not the first time that I have this problem. After minor corrections of photos taken by me, I want to upload the new versions in Wikimedia Commons but since now several months I am unable to do it, last exemple with this image, I got the following message :
"Error

Our servers are currently under maintenance or experiencing a technical problem. Please try again in a few minutes.

See the error message at the bottom of this page for more information.
If you report this error to the Wikimedia System Administrators, please include the details below.

Request from - via cp3060.esams.wmnet, ATS/8.0.8
Error: 502, Next Hop Connection Failed at 2021-06-15 05:44:34 GMT"

And that I start again a few minutes later or at a different day change nothing. It's always the same result. The same as if I try 10 times in a row. I got around the problem by up upgrading the image in Flickr and by uploading the new version from Flickr, and that was done within a few seconds!. But IMO that is not a suitable solution, because 1/ I don't upload all my images to Flickr and 2/ this is an additional transfert of a jpg file and this means that there is necessarily a loss of quality as each time a new jpg is saved.
Note that I'm able to upload new versions on smaller file, so the issue have likely something to do with the size of the file and/or with the time needed to upload.