Test calls or real calls?
Cell phones or landlines?
What country?
In the US, the caller ID Name (which is what you are seeing, not the caller ID number) is controlled by the RECEIVING telephone company. They populate this information with a value from a shared database for registered NANPA phone numbers. In Canada, however, the CallerID Name value is actively passed all the way to the consumer.
If this is a test call, it's possible that the telephone company you are dialing to and from are merely on the same network, and they didn't bother with the "data dip" to get the CID Name value. Try a cell phone or landline, as calling a number to a phone on the same voip company (or on the same server!) is not a valid test for the CID Name field. Or you can just ignore it, as this is not what an actual consumer will see (eg: call your cell, that's a more valid test).
If this is a canadian call, you'll need to use the loopback context to "double-call" and use the 2nd call to set the caller ID name value. But be careful of the truth-in-advertising laws and telemarketing laws in Canada.
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