Amazon Order Stuck - No Delivery or Tracking Update After 6 Days

I ordered two products from Amazon on May 9. Even though I live in Kocaeli, almost a week has passed and the items still haven’t been delivered. I checked the tracking information several times, but there’s no meaningful update. I want to return them, but the system says returns are not accepted—even though I haven’t even received the products. I contacted customer service, but the response was vague and unhelpful. Normally, when I placed orders at night, they would arrive the next morning. If this continues, I won’t be shopping from Amazon again.