There could be several reasons why Free Fire might not be logging in on your Jio SIM:

1. Network connectivity issues: Ensure you have a strong and stable internet connection. Try restarting your device or switching to a different network.
2. Server issues: Garena might be experiencing server problems or maintenance. Check Free Fire’s official social media channels for any announcements.
3. Account-related issues: If you’ve recently changed your account details or password, there might be a temporary glitch. Try logging out and logging back in.
4. Device compatibility: While Free Fire is generally compatible with most devices, there might be specific issues with your Jio device or its software. Try updating your device’s operating system or clearing the Free Fire app’s cache and data.
5. Third-party app interference: Some third-party apps can interfere with Free Fire’s functionality. Try disabling any unnecessary apps and see if that helps.

If none of these solutions work, you might need to contact Garena’s customer support for further assistance. They can provide more specific troubleshooting steps or information about any known issues.