iPhone X (iPhone10,6) (d221ap)(Downgrading iOS 15.5 to 14.3) Restore fail

[EndermanchYT]

BuildIdentity is valid for the APTicket:
IM4M is not valid for any restore within the Buildmanifest
This APTicket can't be used for restoring this firmware
[WARNING] NOT VALIDATING SHSH BLOBS!
[TSSR] Checking BuildIdentity 0
[TSSR] Selected BuildIdentity for request
Variant: Customer Erase Install (IPSW)
This restore will erase all device data.
Device found in DFU Mode.
Sending iBSS (1471381 bytes)...
Cleaning up...
[exception]:
what=ERROR: Unable to send iBSS component: Unable to upload data to device

code=42729540
line=652
file=/Users/runner/work/futurerestore/futurerestore/src/futurerestore.cpp
commit count=290:
commit sha =7f732140187bbcecfed3c34ac38185a4096d06d7:
Done: restoring failed!

[danni551]

I had the same error , you have to check if the iphone is still connected when sending iBec or iBSS because sometimes it disconnects. also check your cable. if the cable is new just retry until it works