Hi,
Try the following
Connecting to the Internet using mobile broadband
1.Tap →Settings→Wireless & networks→Wi-Fi, then touch Wi-Fi to disable it.
2.
The tablet automatically searches for the carrier signal and connects to the network.
When the tablet is connected to a mobile broadband network, the network type appears
in the status bar.
NOTE:
On the LTE/HSPA+ models, if both Wi-Fi and mobile broadband networks are
available, the tablet gives priority to Wi-Fi connection.
''''''NOTE:
If the tablet cannot automatically searches for the carrier signal,
tap →Settings→Wireless & networks→More→Mobile networks→Data enabled to enable it''''''