When reward locking is enabled in the Punchh Platform, the guest's discount basket must be locked. An external ID will be required to lock the discount basket to prevent other channels from creating simultaneous transactions or modifying the discount basket. In this mode, the guest's discount basket must be locked when discounts are applied to a transaction, using a unique identifier external_uid specific to the transaction generated by your application.

The external_uid ensures that no modifications or updates are allowed by any channel (e.g., POS terminals/devices, mobile, etc.) except the application that initially locked the discount basket with the external_uid. Contact your Punchh representative to update this Punchh platform configuration setting.

In some scenarios, such as where a transaction is cancelled or when the guest modifies the order after the basket is locked, the guest's discount basket needs to be unlocked so that transactions can be processed for the guest via other channels (e.g., POS terminals/devices, mobile, etc.). To unlock the discount basket, the external_uid must be passed in the API request along with the user-level access_token of the guest.