Hello, I am Claudeir, a user and independent expert, it is very important to me that all your questions are answered and that you have a positive experience.
-Please test upload any other site, you will probably see that there will be no problems, this is because you are right, this type of error refers to a problem on the server, probably no user is able to upload images to this specific site. So, let's just reset the Edge and check for updates to make sure everything is ok with the browser.
Click the three points in the upper right corner of the Edge, settings, Reset settings. Then, right below, click on About Microsoft Edge, if there are updates they will be installed automatically.
Anyway, try uploading it from another browser to see the result.
If the answer helped in any way, consider leaving your opinion, marking it as answered or leaving more details, so that we can continue the service, this is very important for us.
Sincerely,
Claudeir
Expert