btw: where do you fetch the ID of your item to destroy in your method?
Should be something like this
public function destroy($id, Request $request, Instrument $instrument)
{
/*
* Get the id of the instrument to delete
*/
$instrument = $instrument->findOrFail($id);
if($instrument->delete()){
/*
* Create success flash message
*/
$request->session()->flash('success', '$message');
return back();
}
}