I recently purchased a Q10 from T-Mobile and after using it on their network for a few days had it unlocked. I then placed my work phone’s AT&T SIM in the Q10 which works fine in a 9700 and was unable to get data service only voice. It was my understanding that both the T-Mobile and AT&T Q10s use the same 4G bands so I don’t know why it’s not working. I also went into the engineering screen and changed the radio settings but still no data service on any of my band choices. Any ideas on how to fix this would be appreciated.
It sounds like your SIM card still has the BlackBerry data plan active on it. As far as I know, this data plan only works for the legacy BlackBerry devices. You said that this is your work phone's SIM card that you are using. Do you have the authority to make changes to this account? If so, call AT&T to let them know that you are now using the SIM card in a BlackBerry 10 device. The data plan needs to be updated to be compatible with that device.