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I always thought a Google device would come as unlocked, I know Vodafone cannot add any Vodafone Applications to the phone. Maybe I am wrong and it comes as locked.
As the phone would come on a contract, you wouldn't be able to request the unlock until the third payment had cleared. Please see below.
Or alternatively use a Vodafone Payg sim card in it for 30 days making calls etc and then request its unlock using the new Payg Vodafone account details.
That way you don't have to wait until x3 bills have been paid on time.
To unlock a network locked phone please follow the Nuc Online Unlocking link at the side of the forum page.
This is according to Google and Sim locked pixels 》 https://support.google.com/pixelphone/answer/7107188?hl=en-GB
For example 》 Apple iPhones come locked from Vodafone, but Vodafone cannot add network apps.
Current Phone > Samsung Note 10+ 5G _256Gb > Model: SM-N976B.
Samsung One Ui 2.1 / Android 10.
Samsung Gear s3 Frontier Watch.
Samsung Galaxy Buds.