Welcome to the Asana forum. Sorry you are experiencing the problem, it is indeed frustrating.
I would recommend signing out from both platforms and signing back on.
If the problem still continues to exist, then I suggest checkign with support team on the link below as this should be the case if your project is public.
Yes, I believe this will disconnect everything. What I suggest you do, is sign out of the account… do not disconnect the integration. Just log out and log back into both platforms and then try and look for your project.
Sometimes the integration might require a bit of a refresh and that is all.
sorry to hear that @noe
Unfortunately, at this stage I would suggest you contact asana support and let them assist in the matter as this is not the correct behaviour of the integration.