Calls I Didn't Make

[newportnews]

I activated my verizon account in September.  Every bill has 10 - 15 calls on it from my landline in Virginia to a phone number in Annapolis, Md.  It is always the same phone number.  Each call is always 1 or 2 minutes.  A couple sometimes are 4 or 5 minutes long.  They don't cost anything, becasue I have unlimited calls as part of the package.  But it still doesn't seem right.  Somebody is using my phone line, and I don't know who.  I contacted Customer Support, and they couldn't help.  Is anybody else having similar issues?  Is there a way to block outgoing calls?

[tns2]

Any devices in your config that make make calls?  e.g. alarm systems?

[PJL]

Do you use Verizon's voicemail?

[newportnews]

PJL, Thanks for the help.  I don't have any devices that can dial out.  I do have voicemail set up, and I do get messages from time to time.