I once ordered Xiaomi Redmi 3 (during short sales) , for almost two weeks after scheduled delivery date there was no sign of my parcel , I contacted amazon and they assured that parcel was on way and they set it to high priority, on the other hand the couier person had no idea about my parcel..
I was forced to cancel the order, and day after cancelling the order the courier guy contacted me and said they got my parcel.
I immediately contacted amazon and they told me that once the order is cancelled, i cannot get parcel.. Damn amazon
Though I have to admit, other than that order I never had issues with Amazon, I even got refund for an order I didn't like.