Boult Audio — Airbass powerbud True wireless

So I returned the powerbuds in june which was received by them on 25th June. It was delivered by the courier company, that they arranged. I didn’t hear anything from them for more than a month. Few days ago, I got an email that I’ve sent an empty box which is completely false. Their customer service is blaming me that you should have made a video of packing the product and they have stated that on email which is not. I’m so much frustrated. Their customer service doesn’t even assist the customer and hung up. Don’t even connect with the supervisor. They are 5000. Please, can anyone help me here?