Citibank Credit Card Complaint

Citibank Credit card department,

Billing statement California

- - and Costco ended partnership. They transferred my card to Citi. 60 days later Citi sent me a statement with late charges saying I was late. I called them and they said I owed the $510.00. I asked them for what. They said it was money that was transferred over from - -. I told them I needed to know exactly what I spent it on. She said they would send it to me in a couple weeks. I told her I would pay the bill when I saw it. She said if I did not pay it right away it would hurt my credit. I told her that was ridiculous. I told her I would not pay any bill unless I knew what I spent it on. This seems very strange. I have good credit and always pay my bills on time. I do not like be threatened that my score would go down. I never even knew my account had been transferred over. I want to know that my score was not affected. I do not mind paying the bill, but I think I have the right to know what I spent the money on. They simply sent a bill saying I owe $510.00.