Set up the data plan from the watch setup routine and it will walk you through buying an airtime plan.
Open the Watch app on your iPhone and tap on ‘Mobile Data’.
It may take at least 24 hours, maybe longer and probably not over the weekend.
No iPhone XS Max with iOS 12.3.1
You need to be on 12.3.2 which will allow the latest carrier update and also allow a watch update.
I have just had a watch 4 and connected no problems. YOU MUST update your carrier network settings on your phone before sycning your watch to the phone. If you do not update the network carrier setting on your phone first the watch does not connect to the cellular network. Apparantly you are not alone but the carrier settings update solves 99% of the connection issues.
below are the instructions for doing said:
You can manually check for and install a carrier settings update with these steps:
Hope this helps
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