There are several reasons why your iPhone might be blacklisted:
Before we dive into the solution, it's essential to understand what a blacklisted iPhone is. A blacklisted iPhone is a device that has been reported lost, stolen, or compromised, and as a result, its IMEI (International Mobile Equipment Identity) number has been added to a blacklist. This blacklist is a database maintained by carriers and other organizations to prevent stolen or lost devices from being used on their networks. how to unblacklist an iphone
This method may not work if your iPhone is blacklisted by the carrier. There are several reasons why your iPhone might
Dial *#06# on your keypad or go to Settings > General > About . and as a result