This issue occurs when our app does not fully integrate with the theme. Luckily this is an easy fix. Simply navigate to the Order Lookup Settings page in the app admin.
Simply clear both the Order Number and Email Address fields in the Order Lookup Language section, and then renter the values as you see fit. This will reset them. Click Save Settings on the page to make the changes live. The Labels should now appear on the Order Lookup page.
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