Do I need to return a gifted whoop?

I was gifted a whoop with 2 months free trial. The device doesn’t work for me so I have canceled. I am unsure what to do with the device. The membership page or email I received after cancelling does not state I need to return the device? I don’t want to get charged for not returning!

No. You don’t need to return the device back to Whoop. You can return the device to the person you received it from or recycle it.