I went to that site and tried putting in my promotional code, and it wouldn't let me! It just shows an error message: We're sorry. This survey ID code is invalid. Please ensure the number you typed in has 13 digits with hyphens (XXXXX-XXXX-XXXX). If your code remains invalid, you may contact customer service at (Canada) 1-800-326-2536 or (US) 1-888-818-2536.

The code can't have expired, I got this receipt on February 14! Does anyone know how to fix this problem? Should I just call them?