diff --git a/lib/resources/multiPartyCall.js b/lib/resources/multiPartyCall.js
index 3d3fca8..bcb6616 100644
--- a/lib/resources/multiPartyCall.js
+++ b/lib/resources/multiPartyCall.js
@@ -312,7 +312,7 @@ export class MultiPartyCall extends PlivoResource{
   }
 
   start(params){
-    validParam('status', params.statustoLowerCase(), [String], true, 'active')
+    validParam('status', params.status.toLowerCase(), [String], true, 'active')
     return super.executeAction(this.id + '/', 'POST', {'status' : params.status.toLowerCase(), 'isVoiceRequest' : 'true'})
   }