APR and credit balance discrepancy

Hello, my husband and I have had the Apple Card for a couple years. I just learned that his APR is 10.9% while my interest is 15.9%. I have a higher credit score & FICO rating. We file jointly with similar incomes. I called to ask and was told there was nothing that could be done. If it can't be resolved by elevating the issue, we'll both close the accounts. Has anyone else experienced this? There are several complaints about similar issues and gender discrimination pertaining to this card. Apple is a reputable company and I can't imagine why they would tolerate such issues with Goldman and Sachs.