Images in Outlook Web App are not showing up

Yes, the problem is very inconsistent.
It does not happen with all images, some can be seen as well as some .GIF signatures
It does not happen to all users of Outlook Web, most have not had any problems.
Problems with the browser, computer, or even blocking or network permissions have been ruled out as the same problem has occurred in users who are in different cities.

When downloading any message and reloading the page, all the images of all the emails that had problems begin to be displayed, but this "solution" is temporary since after 20-30min they stop being seen again (they are always the same images).

I got the link of the image hosted at attachments.office.net from the HTML code of the page to be able to interact directly with it. When trying to access that link in another tab, I get the message "Access is denied." If I carry out this same procedure after the method of downloading any message, then it does download the image, as if access were unlocked.

I had the first record of this problem 1 week ago.