Amazon India — Product Cancelled Unnecessary

I ordered redmi note 10s 6 gb 64gb varient for 10999 under a sale going on amazon. They accepted the same and shipped the order. The order was in gurugram and then they marked it cancelled and returned it to the seller. When i asked them about he same they said that it was due to technical issue, then another agent told me that it was not technical issue but the order was returned my me only. I mean how is this possible. They themselves cancel it and then return it and mark it on me. And afterwards i received a email that the order was cancelled as there was a pricing error on the website. The pricing was that the product was of 12999 and a 2000 coupon was there so i ordered it for 10999. After few days a sale came on Flipkart and now I'm getting the same mobile for 10999 without any error. Due to this mismanagement of amazon the whole day wasted. My whole expectations were ruined. Also i would like to tell that on 18th march 12 am sale on Amazon came under which many 20000+ pricing phone were provided with straight 40% off coupon and many people ordered the same. A 26000 phone was costed around 15500 to people. I mean wasn't it a pricing error? And surprisingly almost all and all of the orders as far as i know were delivered to people. If this wasn't the pricing error then how is my mobile for 10999 is a pricing error and when the same is available on Flipkart also.