If the Costume Kingdom coupon code isn't working, consider these steps:
- Check the expiration date to ensure the coupon is still valid.
- Verify the code for any typos or errors.
- Review the terms and conditions to confirm the coupon applies to the items in the cart.
- Clear browser cookies and cache to avoid any technical issues.
- Try a different browser or device to see if the code works there.
- Disable browser extensions temporarily, as they might interfere with the code.
- Contact customer service for assistance if the issue persists.