Cannot preview the images that I have just uploaded after Refresh

[Toan NC]

I often write documents by using Confluence weekly. 
Today I still write and attach images normally, I can see them uploaded correctly (and I can see and check them in the History Page)

However, after refreshing (F5) the browser to ensure the whole page I wrote is there correctly. The images are not displayed, clicking on it will tell that like below.
(I also tried to post the same document on my company area, it's a different account, and I see that it was uploaded correctly. It seems it's only my one, a free account)
Could you help to resolve it?

Something went wrong.
We couldn't generate a preview for this file.
Try downloading the file to view it.

[ Download ] 

[Toan NC · Accepted solution]

After submiting this question an hour, the issue is solved.
Thank you.