I have the insurance ...  does it cover lost drones ?     

If you mean DJI care refresh, it’s not insurance as such I don’t believe.
I think they will review cases where the drone is lost but it’s harder to get your new one. I believe the care refresh is for when you crash (pilot error or otherwise) and still have the drone. Instead of paying for all the repairs the care refresh covers it and you get a referbished Mavic instead.
I’d say open a support call and see what they say? There are people that will read the data file from the mavic and try to help you locate it’s last location on here if you ask/provide the data.
Searching for lost mavic in this forum will point you in the right direction I’m sure.

Not unless you have the State Farm policy that some of us have.

If by "the insurance" you mean DJI's Care Refresh, the answer is no. You must recover and return the drone -- including the camera / gimbal assembly -- to get a Care Refresh replacement.

As Tviscomi already pointed out, though, if you meant that you have a policy through State Farm then yes, it will be covered.

P.S. If you think there might still be a chance of finding your lost aircraft, upload the TXT file from your mobile device to PhantomHelp using these instructions and someone on this forum might be able to make a recommendation regarding where specifically to look.

I'm sorry for your loss, but the DJI Care Refresh will not cover the loss, please check the policy. If you believe the flyaway may caused by malfunction, please contact our support via the link below http://www.dji.com/support to create a ticket, our data analysis team will help to analyze the reason, and will provide the further resolution to you.