Nu Republic — starboy wireless headphones

I purchased nu republic headphones from amazon under one year warranty.
It was bad product and stopped working within few months.
I sent my product for replacement to alchemie.co: service partner of nu republic
Its been 15 days from my complaint registration. They are not informing the status or returning the product.
Details as below :
Invoice number : qwpw-105880
Invoice date : 09.11.2019
Ticket number :5258.
Ticket date :20.02.2020