Open permissions

I have created a custom permission level and have only set it so that people can only open and view files. The issue is that I have been able to open them, edit, and save them. Then when I log out and log back in under my admin account it says that I edited the document a few minutes ago.

I'm trying to make it so that a user can see the documents in word or excel online and be able to download them. However I don't want them to be able to edit the documents. I've done some research and what I've done should be able to accomplish this but it does not for some reason. Any suggestions?