Amazon India - Order Says Delivered and signed but no one have arrived to office and i have not signed.

i had ordered small Item i.e. usb hub from amazon, Was said to be delivered on ** nov Friday but no one came instead got SMS and Email that Product Delivered. was feeling cheated. then contacted Customer care they said parcel is on the way and notification was sent by mistake of scanning machine. I accepted as technology stuff it happens. but then too its ** Monday i.e. *+ days after delivery day also i am prime member. and if mistake of machine ,then why parcel is not yet delivered ? it is clear case of cheating. though amount is small but just thinking what if i had ordered ac or tv of big amount. ?