Why does my Verizon IPhone 6 go straight to voicemail?

I got an iPhone 6 in the summer and for the past month or so, when someone calls me, my phone goes straight to voicemail. I've tried resetting my phone, making sure Do Not Disturb is off, clearing my voicemail, and I've had no success. Is there anything I haven't tried?

In your settings you probably accidentally turned on do not disturb. If you just swipe up at any time you get the brightness and all that. If the moon thing is selected turn it off

There's a section in the settings for call forwarding. Voicemail is technically your calls getting forwarded to a different number. I would check those settings to see if anything is odd. I'm assuming you can make calls?