Hi
I'm sure your inputting the code carefully but please do ensure it's exact along with using an active alternative network sim card.
If it still does not work then this may help....
”You need to remove sim card then enter the code as folow #7465625*638*# ( enter it into the phone keypad and press send)
You will then be asked for the network unlock code - the 8 digit code at the top of your post.
The phone then displayed the message telling me that the phone was network unlocked”
from > https://forum.vodafone.co.uk/t5/Android/Unlocking-Galaxy-S6/m-p/2574468#M138771
Current Phone >
Samsung Galaxy s²³ Ultra 512gb Phantom Black.
