Purchased new t-mobile sim card to put into an older iPad 3 and the previous sim card was moved to a new iPad Air. If I turn off wifi, cellular data does not work. Does the new sim card need to be activated? I thought it would have been activated at the t-mobile store when I bought it. I do see the SIM card number in IPAD but no phone number is listed (I know the phone number by looking at t-mobile acct).
It does sound like the SIM does need to be activated. You can give Customer Care a call at 611 to activate it.
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