Citibank Credit Card Complaint

Citibank Credit card department,

Sale of account California

I am a Costco Executive member. They offer a credit card thru -. I had - but Costco Switched mid year to CitiBank visa -/-/16. On -/-/16 I checked my account and it was locked, and it told me to contact Citi regarding fraudulent charges. There was a fraud charge in -, AZ at a -. I told them to close the account. Citibank refuses to pay me my cash rewards from -/Citi that I accrued, their reason is because I closed my account. THIS IS THEFT!!!! MY REWARDS WERE MOSTLY FROM - PURCHASES ( PRIOR TO -/-/16 ). CITI IS NOT ENTITLED TO MY REWARDS CASH. THEY ARE STEALING FROM EVERY PERSON THAT CLOSES THEIR ACCOUNT.