I got an error when I tried opening my game. It said check my internet connection and check that my browser accepts cookies. Ive spent a lot of time on the game so far and would hate for it to be lost. Is there some way to open it up

I assume you have a cloud project. According to the last post in this topic: [Solved] My project IS JUST GONE you should “contact a team member with your GDevelop username and project name.”