Express bees - Product changed

I applied warranty claim for my smart watch (boat storm pro call charcoal black) in boat company which was picked up by expressbees courier company after picking up my smart watch and before reaching boat company for claiming my warranty before that my smart watch has been changed, I don't know who's change the item, maybe a courier boy change the item, but when I talked to the expreesbees courier company they told me we will investigate in the same but they are don't take any action about that, however I have gave them a video proof and pdf image which was received from boat company.
Sir I have request to you please resolve my problem as soon as possible,
I just want to return my smart watch or compensate me.
For your reference I have attached the video proof and pdf image.