A word to the wise: check your phone bills carefully to make certain you are not getting 'slammed' by the absolute sleazebag company known as Operator Assistance Network (OAN).
My November phone bill from Verizon was the second time in six months I had a totally bogus charge from OAN passed along to me. The first time it was $7.00 for "directory assistance"; this time it was $14.95 for "voicemail service".
In neither case did we ask for or use these services. In both cases I informed Verizon I did not intend to pay this bogus charge, and Verizon was actually fine with that. I also filed on-line complaints with both the Federal Communication Commission and Federal Trade Commission to report OAN (and I actually got a follow-up from the FTC and from OAN).
OAN will remove the charge if you call them are firmly tell them you have no intent, eve, of paying. I would also suggest you arrange with your phone service provider (Verizon in my case) for a "third party bill block". This means that your provider will not accept and pass along on your bill charges from any outside company such as OAN. It may take a few minutes of your time when you call your phone company to do this, but just not to have the aggravation of bogus charges from the likes of OAN it is well worth it.
OAN is without a doubt the sleaziest bunch of scumbags it has ever been my misfortune to run across. Check your phone bills, dispute any such charges, and file reports with the FCC and FTC.