This person called me. I don't know who it is.

I think this may be the Verizon Wireless billing dept. (my bill is overdue)
PhoneValidator.com and whitepages.com/phone/1-360-450-4348 show it as the same location (Vancouver, WA)  and carrier (Level 3 Communications) as:
360-553-4260
360-975-4463
360-975-4426

They do not leave a message.

Also the same as  whitepages.com/phone/1-360-450-4636
They probably have a zillion numbers with VOIP

I'm going to guess the above comment is correct because my Verizon bill is also overdue. My husband for some reason always pays the month after instead of the month ahead...so we're always behind lol. I'm glad I didn't answer because my guess was that it was them.