Hi uyildiz0,

I'm sorry to hear you're experiencing this issue!

Here's a few things you can try:

• Use Khan Academy with the latest version of Google Chrome
• Clear your cookies and cache
• Restart your device
• Update your browser and software
• Try using a different internet connection

If the issue persists, please submit a support ticket so we can further investigate the issue.

I hope this helps! Please let me know if you have any additional questions!