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My Apple Watch was working fine with mobile data, until I replaced my iPhone. I was away from the UK at the time, so I was not using Vodafone mobile data with the watch. I no longer have the old iPhone. I have tried unpairing and also tried erasing all contents and settings, but I still get the "Unable to activate mobile data" error every time. I have the most recent OS updates on both the iPhone and the watch. Please help!
It could be that you need customer service on 191 or Live Chat with account access @david314 to check things at their end.
Unfortunately there is no account access via this forum anymore.
The Vodafone Social Media Teams via Contact-us-for-account-specific-queries also have account access too.
I wish you all the best with this situation.
Current Phone > Samsung Note 10+ 5G _256Gb > Model: SM-N976B.
Samsung One Ui 2.0 / Android 10.
Samsung Gear s3 Frontier Watch.