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How does my daughter set about unlocking my old Vodafone phone for use with an 02 sim
You would fill out the following unlocking form @hectorjcampbell
Vodafone would then confirm by return email if they accept your request and then send a Nuc.
Check the criteria set out in the link above.
You then put in the other network sim card which would invoke a pop up box to input the Nuc.
Current Phone > Samsung Note 20 Ultra 5G - SM9860 Snapdragon.
Samsung One Ui 3.1 / Android 11.