Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
What model is your Fanvil phone, an X5, and X3, or some other model, please ?
Have you gone through the Configuration Wizard properly, to set up the phone? this is important. If you have not done so, I advise you to do so. To re-start it, just factory reset the phone, and it ought to appear automatically. (For factory reset instructions, let me know the phone's model #.)
(In general, you may go to Settings - Configuration Wizard, without resetting the phone, to go through Configuration again.)