Flipkart — Item delivery status and return

On 31st Aug i received wakefit 6-inch mattress with 78x72 dimensions. After receiving the product i realized it doesn't fit my bed so i wanted to replace with new size. When i called flipkart since on app delivery was not even showing on Flipkart app i was not able to raise a request for return/replacement.

Today after 5 days Flipkart customer service saying to me we still dont have update on item delivery.
On 31st Aug itself i informed them i am going out of station for 3 weeks on 8th sept morning. but there is no according action from flipkart side.
order ID : OD[protected]