Flipkart — product delivery and purchase

I was purchased women's watch on 6 aug and the delivery date was 10 aug however product was not received on time and in 13 aug i got a massage stating that your order has been cancelled and refunded, how it was cancelled without customer concern.

No intimation
No on time delivery

My second query: i was tried to purchase another product from flipkart and delivery date was mentioned as 14 aug, after making the payment the delivery date was changed to 16 aug, so how could they changed the date