iPhone X doesn’t ring when caller is not in my contacts

My iPhone X will not ring or light the screen up when someone not in my contacts calls. The call goes right to my voice mail. Apple had me update software and set phone back to factory settings. Still happens. I removed my spam blocker apps and it still happens. The first I know someone called is when I get the sound notification that I have a voice mail and that can take a few minutes to 20 minutes for the voice mail alert to sound.