Try reprogramming the phone to the Verizon Wireless network. Dial *228, option 1.
I would be upset too, if I couldn't get the VZW network and had to rely on Wifi! Thanks Ann154 for your input! I'd like to add to that and give you some troubleshooting steps. Please go to Menu>Settings>Data Manager>Data Delivery. Make sure that the following are checked: Background Data, Data Roaming, and Data Enabled.
Please let me know how this works out for you. Thanks much!
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nice of you to offer help 17 days after question was asked.