Received a letter from debt buyer that said I owed 5k and demanded I pay on it. They included a page showing the amount from the original card company, the interest rate charged and the ending balance from the card company of 3k. When it was sent to their attorney, the attorney lowered the amount I owed, and were seeking to 3k and sent me a letter saying I needed to pay the whole amount (not reduced). They changed it on my Credit Report saying I owe 3k. Now they have sent me copies of my last statement, card agreement to validate the amount. Is it ok that they first demanded I pay the 5k even though now they changed the amount to 3k with the validation?