Kindly try these steps when your promo code does not work:
Check terms and conditions of the code if it is still active.
Check if your order meets the promo criteria because some promotions are only applicable on certain items and specific email addresses or exclusively for new customers.
Make sure that the code has not previously been used.
Ensure that you are applying only one coupon at a single checkout.
In case all of the above are correct, please take a screenshot of the discount code you received and send it to support@trendingcustom.com. We will assist you further.