Doesn't matter, they should be doing their homework before calling numbers.  Well known criminal debt scammers here.  You also have to understand that debt collectors don't care if you owe the bill or not, they simply want someone, anyone to pay them.

You need to send them a certified, return receipt debt validation (by law they have to go back to the original creditor to prove you owe the debt), cease and desist calling, or "not me" letter (think of it as the best $6.59 you ever invested).  Also send it first class mail in case no one will sign for it.  Make a notation of that fact at the bottom of the letter.  You also need to report them to the proper agencies to which I have provided links to.  Then you need to go out and get a consumer lawyer to sue them on a contingency basis (no money out of your pocket) and let them pay you for the harassment.  If everyone did these three things, these crooks would be bankrupt and we would all be the richer for it.  Use these web sites to find an attorney in your state that will probably take the case on a contingency basis (no money out of your pocket up front):  http://www.consumeradvocates.org/
http://www.consumeradvocates.org/find-an-atto ... tates_value=All

Everything else you need to know follows including at least two agencies where you should report their criminal activities.

COLLECTION BUREAU OF THE HUDSON VALLEY
Alternate Business Names
CB / HV, CB/HV, CB/HV, Inc. , CBHV,  Healthcare Billing Service of NY Inc.
Number threads associated with these crooks:  http://800notes.com/Phone.aspx/1-845-913-7499
http://800notes.com/Phone.aspx/1-845-561-1395/2
http://800notes.com/Phone.aspx/1-888-913-7443
http://800notes.com/Phone.aspx/1-888-913-7496/2
http://800notes.com/Phone.aspx/1-914-499-3669

Web site gives physical address:  https://www.cbhv.com/contact-us/
BBB gives them an accredited A+ with 13 complaints (11 complaints were removed when the accreditation was applied) and 1 negative review: http://www.bbb.org/new-york-city/business-rev ... wburgh-ny-27161
This document list the Treasurer as an employee of CBHV:  http://www.nyscollect.org/AffiliateMemberBenefits2015rev.pdf
This is an interesting read:
http://www.pibillwarner.com/2012/06/bolowatch ... k-and-cbhv.html
Some interesting information on some of the head criminals at this enterprise:
https://www.visualcv.com/ericnajork
http://www.zoominfo.com/p/Thomas-Kavanagh/2263334
https://ericnajork.wordpress.com/
New York Dept. of State info:
________________________________________
Selected Entity Name: COLLECTION BUREAU OF THE HUDSON VALLEY, INC.
Selected Entity Status Information
Current Entity Name:    COLLECTION BUREAU OF THE HUDSON VALLEY, INC.
DOS ID #:    420221
Initial DOS Filing Date:    JANUARY 06, 1977
County:    ORANGE
Jurisdiction:    NEW YORK
Entity Type:    DOMESTIC BUSINESS CORPORATION
Current Entity Status:    ACTIVE

Selected Entity Address Information
DOS Process (Address to which DOS will mail process if accepted on behalf of the entity)
COLLECTION BUREAU OF THE HUDSON VALLEY, INC.
155 N PLANK RD
NEWBURGH, NEW YORK, 12550-0831
Chief Executive Officer
ERIC NAJORK
155 N PLANK RD
NEWBURGH, NEW YORK, 12550-0831
Principal Executive Office
COLLECTION BUREAU OF THE HUDSON VALLEY, INC.
155 N PLANK RD
NEWBURGH, NEW YORK, 12550-0831
Registered Agent
NONE
Bizapedia info:
Company Name:      COLLECTION BUREAU OF THE HUDSON VALLEY, INC.

File Number:      420221

Filing State:      New York (NY)

Filing Status:      Active

Filing Date:      January 6, 1977

Company Age:      38 Years, 10 Months

Registered Agent:               Collection Bureau Of The Hudson Valley, Inc.
155 N Plank Rd
Newburgh, NY 12550-0831

Principal Address:               155 N Plank Rd
Newburgh, NY 12550-0831

Mailing Address:               155 N Plank Rd
Newburgh, NY 12550-0831

Company Contacts
ERIC NAJORK

Chief Executive Officer

155 N Plank Rd
Newburgh, NY 12550-0831

Looks like they get sued a lot:
https://dockets.justia.com/docket/new-jersey/njdce/2:2013cv04218/291792/
http://www.law360.com/cases/53bd623a26cdbf3924000002
https://pacermonitor.com/public/case/9898209/ ... son_Valley,_Inc
https://pacermonitor.com/public/case/9926209/ ... son_Valley,_Inc
http://www.law360.com/cases/512fb681d486587d73008c4e
http://www.gpo.gov/fdsys/pkg/USCOURTS-alnd-2_09-cv-01149
https://casetext.com/case/oslan-v-collection-bureau-of-hudson-valley
http://www.plainsite.org/dockets/4n7sss15/new ... son-valley-inc/
http://www.law360.com/cases/5317677ed0a47d237700ad96
Other complaints:
http://badfinance.org/review/1429027/collecti ... debt-collection

It is incumbent upon them under the law to prove that the debt exists and that you owe it, and that they have the legal right to collect it.  You are not obligated under the law to prove that you don’t owe or that it is paid.  

Federal law (FDCPA) requires them to send you a letter (US MAIL ONLY) postmarked 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 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://800notes.com/faq/attorney-general

File a complaint at the NY State AG's Office here:  http://www.ag.ny.gov/