As a requirement from Apple, all iPhones participating in the Stacker Market Pro Account card program has to be approved by Apple Inc.
Note: If you are planning to use another iPhone after the current iPhone's SEID has been approved, you will need to make a new submission of that other iPhone's SEID to be approved by Apple Inc.
Read on for the step-by-step guide to retrieving your SEID.
Open your iPhone’s Settings. Check the Utilities folder if you don’t see it.
Scroll down and tap on "General". You may have to scroll down 1 or 2 screens to find it.
Tap on "About".
Scroll down and tap "SEID". You will find it near the bottom of the list.
Long press the SEID and click on "Copy".