Apple’s signing servers or 3uTools' own servers are temporarily down. How to Fix "Unable to Request SHSH" 1. Update 3uTools to the Latest Version

The "Unable to Request SHSH" error generally stems from these common issues: The iOS Version is "Unsigned":

A: As with any third-party tool, use caution when working with 3utools. Be sure to follow the instructions carefully and backup your device before making any modifications.

A firewall or an unstable internet connection can block the request to Apple’s servers.

: Use an original Apple lightning cable and a different USB port to rule out data transfer issues.