yii2 rest - using PUT to update data - yii2

Question

I am using a REST API in Yii2 with Authorization Bearer
I have configured the actionUpdate completely but somehow when using PUT to update the data, I am getting null value when I try to get the post data,
print_r($request->getBodyParam('member_id'))
Get below result when print_r(Yii::$app->request->bodyParams):
Content -type is multipart/form-data
Array
(
[------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition:_form-data;_name] => "member_id"
274505
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="claim_type"
3
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="visit_date"
2016-10-12
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="provider_id"
0
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="diagnosis"
fevercc
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="reimbursement"
1
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="non_panel"
true
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="provider_name"
klinik abc
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="reimbursement_reason"
near to house
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="invoice_no"
1245
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="medical_leave"
0
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="leave_form"
------WebKitFormBoundaryAF3YWAApi5BxYUb2
Content-Disposition: form-data; name="amount_incurred" 24
------WebKitFormBoundaryAF3YWAApi5BxYUb2--
)
Below is my actionUpdate
public function actionUpdate($id) {
$claim = $this->findModel($id);
$claim->scenario = 'update';
if ( $claim->status_id == 1 ) {
$request = Yii::$app->request;
if (isset($request)) {
$member_id = $request->getBodyParam('member_id');
$claim_type = $request->getBodyParam('claim_type');
$visit_date = $request->getBodyParam('visit_date');
$provider_id = $request->getBodyParam('provider_id');
$diagnosis = $request->getBodyParam('diagnosis');
$reimbursement = $request->getBodyParam('reimbursement');
$userlogin_id = Yii::$app->user->identity->id;
if ($claim->validate() ) {
$claim->save();
return array('id'=>$claim->id,'msg'=>'Successfully update claim');
} else {
return (ActiveForm::validate($claim));
}
}
} else {
throw new \yii\web\MethodNotAllowedHttpException('You are not allowed to update data');
}
}