USAA Savings Credit Card Complaint

USAA Savings Credit card department,

Billing statement Virginia

My credit card made a special zero % financing offer that I accepted & then they charged me interest every single month. I have called them 3 times & each time they have told me they are in the process of the resolving the issue & that I should see a statement credit soon. It 's been 6 months & I have not. They have also switched this card from being a - to a -. I am worried that this will get lost & never be resolved.