The message they left said they are a bill collector but I don't owe any bills.  I blocked it.  Received it on my cell phone.

It would ahve been nice if you had told us the name of this DC company.  If they left a message, this is what they must do by law:

Federal law (FDCPA) requires them to send you a letter (US MAIL ONLY) within 5 days of their first contact that contains their name, physical address, the creditor’s name, and the amount of the alleged debt.  It also must contains “mini-Miranda” telling you that it is an attempt to collect a debt and that all information will be used for those purposes.  The one other important thing that this letter must also have in it is that you have a right to dispute the debt within 30 days of receipt of the letter and if you do so, all collection activity must be stopped until the debt is verified.

Read up on your rights here, get template letters to send and also make a complaint at this government site: http://www.consumerfinance.gov/

Also file a complaint with your State Attorney General's office.
List of State AG’s offices:  http://consumerfraudreporting.org/stateattorneygenerallist.php

fresh debt solution, debt collector

Do you have an address for this "company"?

Scammer using fake phone numbers to harass people.  Do not answer - block caller.