Hello anyone reading this thread or have a smiliar problem. I think I found the solution for that kind of message. Probably a solution that @WarrenBelz already posted somewhere in this forum but I'll post it back here in case.
(Sorry for the french interface but in english or whatever your language is, it will probably be about the same.)
First click on the publish buton and click on "Modify details".
Once you reach the settings, click on the last options on the right which would be "Assistance". Then look at the "Creation version". I was looking at the list of my previous published version and noticed that they had changed the version numbers right before I started to get that problem. Click "Modify" and switch it back to the last version where your application was working.
Mine was this version and then click "Publish that version". When I went back the "Read" mode, my application opened like nothing had happened.
Thank you @WarrenBelz for your help.
