The SIM card allows the phone to work on the cell network. The micro cell only forwards calls via your DSL or other network. The number on the phone display? Is the phone really unlocked? Go to the top of the forum and to the FAQ section for info on verifying if it's unlocked.
the SIM is where the phone get the number so are you sure you have the correct SIM in?

This may work but keep in mind the network number and SIM number must match. simply changing the display number wont do anything if it's not your number.

Step 1 - The smartphone draws the phone number from the SIM card. If the information is not populated or is not correct on the SIM card, the smartphone will show the phone number as Unknown or the wrong number

Type the phone number on the SIM card.

Make sure the smartphone is running the most recent version of the BlackBerry® Device Software.
From the Home screen of the smartphone, click Options.
Click Advanced Settings > SIM Card.
Highlight the phone number.
Display the menu and click Edit SIM Phone Number. If this option does not appear in the menu, see Resolution 2.
Enter the correct phone number, and then click the trackball or trackwheel.
Restart the smartphone. The phone number should appear in the Phone application.

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