Ecom Express — Non delivery of package and rude service from delivery manager

I have ordered an item from IFFCO eBazar online. The package was picked up by EcomExpress on 12 OCT 2023 and is still undelivered. I have received multiple messages on my mobile that the package was undeliverable without anyone contacting me. When I called the mobile number of the delivery manager that was provided to me in the message from EcomExpress, I was told rudely "I am not a delivery boy" and the phone was hung up. I have written to both IFFCO and EcomExpress and have received no response.
EcomExpress support number provides only an IVR response and no personal interaction. Registering a complaint with them has not helped either. I have requested a refund from IFFCO Bazar but they have not bothered to respond.