Download a version that is still signed and try again.
and verifying it against signing databases like sh.host.io may help identify if the firmware version is still valid for your specific hardware. Restore via DFU Mode : If Normal or Recovery mode fails, put the device into DFU (Device Firmware Update) Mode how to fix error unable to request shsh on 3utools when upd
You're looking for a solution to the "Unable to request SHSH" error on 3utools when updating. Here's some interesting content that might help: Download a version that is still signed and try again
If 3uTools keeps failing, use (web-based) or Blobsaver (desktop) instead. how to fix error unable to request shsh on 3utools when upd
If you are using the standard update method and failing, try the alternative flashing modes within 3uTools.