This is the 'direct'; or back-door number for a collection agency company that buys old, bad debts, and tries to activate them.  The firms name is "Client Services"
Their auto dialers they use today include:
925-452-4853
636 -947-3495
636-947-2321
636-410-7624
(If they call you with the '925-' number call them back with the back-line number and [***] slap them.)
This  'services' (collection company) have a number of workers; they pick-up DEAD debts.  IF you havn't paid anything towards it in 5-years, it is legally a DEAD debt. (Except for School Loans - sorry- which never die, even after bankruptcy);....  IF they can get you to pay SOMETHING, anything, then the debt is raised from the dead, and the clock starts AGAIN, and becomes collectable.  DO NOT PAY ON DEAD DEBTS.  
This collection agency gets 50% or more on dead debts they succeed in activating. Interest on a $15.00 dollar debt can be $1,200.00 after 5 years!

They also will chase the WRONG person. Again,the number to call to complain about this is the feds (see below) or THEIR backdoor number: 636-947-2321. With a name like "Client Services", you can expect them to be cagey when you call; do not give them personal information about you, or anyone else at your number; simply reply to their question(s): "what information do you have?"

You can also put your number on the Federal no call list,at: www.donotcall.gov/