If your coupon is showing as invalid with the code "SAMPLEONLY," you need to replace it with a valid code before launching your campaign.
Quick checks
Has the default placeholder coupon code "SAMPLEONLY" been replaced with a real code?
Did you edit the Coupon component on the correct display's "Thank you" page?
Cause
"SAMPLEONLY" is the default placeholder set when a coupon component is added to a display. It must be replaced with a real coupon code before launch.
Steps to fix
In the display editor, open the "Thank you" page and click the Coupon component.
Click the Edit button and enter your coupon code.
Still not working?
If the issue persists, contact us via live chat. Please include your display name and the coupon code you are using.