calling use all the time - please someone help me stop them

got a call from this number at our business.  asked for someone who worked here years ago and hung up when told they were no longer at this office

they called almost every week and when finally answered they asked us to fax some pages of our phone bill. they claimed to have the ability to give us discounts on our bills. needless to say that we never faxed such information because it was rather suspicious. are they for real or what?

Even though we are listed on "no-call" lists, this number still called us.  Telemarketing call - phone service solit.

telemarketing call to my business phone. Phone service solicitation.