Mivi — Company not giving my replacement product, unethical behavior from company

I have purchased Mivi coller 2 dated 11th Mar and received the shipment on 15th Mar.
It was worked for 3 months, suddenly both side of earphone stopped working.
Below are some product details
Product Name - Mivi Collar 2B wireless.
Order date - 11th Mar 2021
Order ID[protected]
Contact Name - Sandip More

I am taking continuous follow ups from MIVI but they are not responding to my mails as well as calls. I am really frustrated. Its been around 1.5 months now and I am still don't have any idea about my product.

This is the last option I can see to get my product back.
Attached is the invoice and our mail communication for the same.