Damon, I read your initial post carefully, thoroughly, repeatedly and quite literally. You have failed in communicating what the contents of the 2 letters from them contains. There is a rather large assumption being made between you "received 2 letters" and "have to pay." Perhaps sharing the wording would help.
Printed copy · Anthology Volume 5, page 687Printed copy from The Tender For Law Anthology, Volume 5, page 687 (printed 13 June 2014). Added by this site; not part of the Facebook export.