We recommend the following several steps:
- Refresh the game page with a combination of buttons Ctrl+F5 (Cmd + R for Mac).
- Clear the cache of your browser.
- Make sure that your browser has been updated to the latest version.
- Try removing the game from the list of its applications, and then return it back (all your achievements in the game will be preserved).
- Try using a different browser.
- Also, the game can be blocked by various extensions in the browser. Try turning them off for a while.