Laravel Resource is empty - laravel

Question

I'm passing data to these functions via Axios/Vue. The Eloquent interactions work perfectly. When I store (i.e. create a new call) the resource returns as expected. When I update a record, it updates in the database, however, I get a blank response. In other words the return new CallResource($call) returns nothing. I can't work out where I've gone wrong.
public function store(Request $request)
{
$call = $this->validate($request, [
'title' => 'required',
'job_id' => 'required',
'location' => 'required',
'starts' => 'required|date|before:ends',
'ends' => 'required|date|after:starts',
'rate' => 'required'
]);
$call = Call::create($call);
return new CallResource($call);
}
public function update(Request $request, $id)
{
$data = $this->validate($request, [
'title' => 'required',
'job_id' => 'required',
'location' => 'required',
'starts' => 'required|date|before:ends',
'ends' => 'required|date|after:starts',
'rate' => 'required'
]);
$call = Call::find($id);
$call->update($data);
return new CallResource($call);
}
The call resource is really simple
class CallResource extends JsonResource
{
/**
* Transform the resource into an array.
*
* #param \Illuminate\Http\Request $request
* #return array
*/
public function toArray($request)
{
return [
'id' => $this->id,
'title' => $this->title,
'location' => $this->location,
'starts' => $this->starts,
'ends' => $this->ends,
'rate' => $this->rate
];
}
}
Laravel 5.6 fyi.