Try these steps:
1. Refresh the page — Extensions only activate on pages loaded after installation.
2. Check the toolbar — Click the puzzle piece icon and ensure the extension is enabled.
3. Check for conflicts — Disable other extensions temporarily.
4. Update Chrome — Ensure you're on Chrome 110 or newer.
5. Reinstall — Remove and re-add the extension from the Chrome Web Store.
If none of these work, contact support with your Chrome version.