Unable to make outbound calls to a number: "Not Found" error message

Error when calling from your GreenLink phone to an outbound number prompting: "Not Found" and calls being marked as SPAM.

When you are unable to make outbound calls to an outbound number and keep getting a "Not Found" response and call drops. Also, in the VoIP Monitor, it shows the call being "rejected by Call Protect."

This is why it happens and how to prevent it from happening in the future: 

The "Call Protect" is the term end-carrier (the carrier/phone company that provides the phone service to the number you are dialing out to) blocking the number because they are seeing it as SPAM (any kind of unwanted or unsolicited form of digital communication). 
In order to ensure your outbound calls are not miscategorized as unwanted or fraudulent calls by the wireless carriers, we highly encourage you to proactively request authorization of legitimate outbound calling use cases from each of the major wireless carriers.
Below are websites where you can submit whitelisting requests:

We recommend that you start at https://www.freecallerregistry.com/fcr/ and, if needed, use the other whitelisting links provided.