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Did you get any instructions along with the Nuc from Vodafone on how to use it ?
There is some info in How-do-I-use-my-nuc.
Sonys Official Unlocking Informational page is My phone is operator locked. How can I unlock it ?
It does seem from previous posts on the forum that a few people have experienced issues when unlocking a Sony Phone.
Some of the examples are.....
There are more examples via a forum search.
May I assume your alternative non Vodafone Sim Card is activated i.e connects to mobile data etc ?
Only so many wrong attempts can be made to unlock the phone thus if too many are made the phone can Hardlock which means a Nuc won't work then until Vodafone have sent it away to be reset. Please see some of the information in the above links on how to check how many attempts are left.
"To check the number of attempts for Network Unlock Code (NUC)
Remove any SIM card from the Xperia device.Turn on the device.
Dial *#*#7465625#*#* to access the service menu.
Tap Service info → SIM lock.Look for the 'X' mark.
If 'X' is on Network and the value is different than 0, you can remove your device's operator lock."
And your currently in the Uk ?
Vodafone Customer services on 191 or Live Chat can have the Nuc checked.
So can the Vodafone Social Media Teams via Contact-us-for-account-specific-queries.
I'd suggest Twitter.
Please link back to your thread here including your forum username so your not having to repeat yourself.
I wish you all the best with this situation.
🌈 Stay Safe & Stay Alert. 🌈
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