I ordered the Accu-Chek Instant Test Strips (50 Count) in Oct 2025. Initially, two strips worked fine, but soon after, my glucometer started showing an E-11 error on every test. I checked multiple times and even tested on other family members, but the error persisted. Later, I found that this error means the strips are defective.I tried reaching out to Amazon, but since the item was marked non-returnable, I couldn’t raise a complaint easily. When I finally managed to contact customer care, they said the return window had already closed, even though this was never clearly mentioned on the product page.I have wasted around 15 strips and nearly Rs. 1,000 on a product that’s not usable. This is very disappointing, especially for a medical item where reliability and authenticity are crucial.I’ve purchased Accu-Chek strips from Amazon before and never faced such an issue, but this experience has seriously shaken my trust. I hope Amazon and the seller look into the product quality and replacement policy for defective medical products.