That sounds strange.
Is there any chance they might've gotten deleted from your Customer List by accident?
Nothing outside of a manual removal would cause this, so we might need to take a look at this with you to find out what happened.
I'd try using the "Redeem Reward" search function in the app to see if their rewards still come up with the email address or phone number.
If that doesn't work, reach out to our Support Team and they'll be able to walk through it with you.
