Can't see uploaded files on digital ocean

I have Node.js project on Digital Ocean. There fileupload function. When I use Microsoft Azure it works fine. All users around the world can see uploaded files (for example, images). But when I use Digital Ocean, it works pretty strange. Case: I upload images to server. Ok, images were uploaded. I can see them. But when other user #1 (as I understand not in my network or I don't know, it's a very very strange) tried to see my images, he can't do it (server says that there are not images with address from DB on this server). Well, then this user upload images, and now I can see only my images, but I can't see he's images. I tried to see which files stored on server, so there are only my files, not files of that user. Then I asked one more user #2 to see images on my server. And this user also had only my images, not images of user #1. Well, then I tried use IP of other country. And again, I can see only my images.

How can I fix this very strange trouble?

UPD: I asked user #3 to do the same things. And he also can't see my images and images of user #1. He gets only his images.

via Denis Worker