If your Coupert extension is greyed out and not working, follow these steps to troubleshoot and resolve the issue:

1. Restart the Browser: Sometimes, simply closing and reopening your browser can resolve temporary glitches.

2. Check the Tab Compatibility: The Coupert extension may not be active on certain websites or tabs. This can happen if the page does not support coupon applications. Try navigating to a different site known for offering discounts to see if the icon activates.

3. Re-enable the Extension:
- Open Chrome and click on the three dots in the top right corner.
- Navigate to More Tools > Extensions.
- Find Coupert in the list, and toggle it off and then back on to re-enable it.

4. Check for Updates: Ensure that your browser is up to date. An outdated browser might hinder the functionality of extensions.
- In Chrome, go to the three dots > Help > About Google Chrome. This page will check for updates.

5. Clear Browsing Data: Clearing your cache and cookies can resolve conflicts.
- Go to the three dots > Settings > Privacy and security > Clear browsing data.
- Select "Cookies and other site data" and "Cached images and files," then click Clear data.

6. Reinstall the Extension: If the issue persists, uninstalling and reinstalling the extension might help.
- Go to the Extensions page, find Coupert, and click the Remove button.
- Visit the Chrome Web Store, search for Coupert, and reinstall it.

7. Check for Conflicting Extensions: Other extensions might cause conflicts. Try disabling other extensions to see if Coupert starts working again.

8. Review Coupert's Settings: Some settings within the Coupert extension can impact its functionality. Consider resetting or checking its options for any restrictions that might be in place.

9. Contact Support: If none of the above steps work, consult Coupert's support for further assistance with troubleshooting issues specific to their browser extension - learn more - learn more.

These steps should help identify and fix the reason your Coupert extension is greyed out.