Bank of America Credit Card Complaint

Bank of America Credit card department,

APR or interest rate Missouri

I made a balance transfer awhile back for a 0.0 % interest rate until -/-/- with Bank of America. I owe $7700.00 of - on it. I have not used it for purchases for many years. I 've made payments by auto-deduction from BoA. I was stuck at the last minute for a business trip and bought an airline ticket, -/-/-. As soon as I was reimbursed, I paid it to the credit card. Since then, I kept having missed payments, and the minimum payment was always very different. Today I made another call to them, and was told I have 10.49 % interest on my airline ticket purchase. I said I thought the payments went to the highest interest rates first. He told me since the government has changed the credit card regulations ( or something like that ) the opposite was true. Is this true?