Showing up on my usage details over and over again

I need some urgent help. I connected the fios triple play on October 30,2015. The next day on my usage details a {edited for privacy} number shows and beside it , it states the word VOICEMAIL. I never set up my voicemail, never checked my voicemail. The only reason I got the phone was to receive the 300 giftcard. So again i have no phone hooked up to the house and no one is home during these calls. It does not say if they are incoming or outgoing. Even without a phone I was getting calls as it shows on my bill. But none where picked up.I need help to figure out what that number is . It only shows on Voice Usage details .

Again I have no phone hooked up...not home when these calls happen ...

On one more note i recently saw this usage details call log after my phone was disconnected out of curiosity. Can these be calls that went to my voicemail. They started October 30,2015 and ended January 10,2016. Alot of them throughout the month.