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In my platform notification, I'm receiving "CustomCode" for a shipping service instead of what I expect. How can I get the expected value?
The likely cause of this is that the expected value was introduced in an API version which is later than the payload version of the payloads you're receiving. You can check the payload version we're sending in the payload with a call to GetNotificationPreferences.
By default, we set the payload to a low version so everyone is compatible (to some degree). However, by doing so, we send "CustomCode" if the payload version is not high enough.
Use SetNotificationPreferences to set the payload version to a higher level to receive the "real" value.