Where the validation code appears
When the current invitation provides a code, it is usually displayed on the final confirmation screen after all required answers have been accepted. Let the page finish loading and scroll to the end.
Where to write or store it
Many invitation receipts include a blank space for the final code. Write it clearly, keep the original receipt and make a private screenshot as a backup. Do not publish the code online.
What to verify before redemption
Read the exact item, required purchase, participating restaurant, deadline and original-receipt requirement. A code alone does not replace the printed terms.