My customer is using TPS2546, But when the product been sent to US to authenticate, they found TPS2546 can't be recognize: They use two device to charge iphone6s, ipad pro, ipad mini4 and found one device can't charge for ipad mini4. They test it in field and found they can charge for iphone6S but it is failed to charge i[[hone6.Could you give some suggestion and idea to solve it?