Problem with the cover image

I add an image (1600x600) to the cover and when I want to change it, it does not change easily despite clearing the cache on the PC with Ctrl+F5 and Ctrl+R. I have made more than 30 attempts and it does not change. After 30 minutes, then by clearing the cache, the change is possible. Of course, a user would not have the patience to do the same. It immediately disappears. What could be wrong and how can I fix it?

Easiest is to add ?v=xyz to image url where xyz is random string like timestamp.
Alternative would be to name images with random string.

Who implements this solution? The website administrator? And how is it done?

If you mean that every user will do what you suggest, no one is going to do it

Plugin was updated, please check.