A user must be created before adding a conference.
If you are interested in being able to host conferences for more than 3 people, then implementing a Conference Bridge may be a great option for you!
To get one set up, please reach out to our technical support team by calling 844.59PRIME (844.597-7463), dialing HELP/4357 on a desk phone, or emailing support@primecall.com
The two calls should now be joined in the conference.