How to passt Json Object list as a parameter in Web API

Hey Guys , 

 

I have made an api which receives the list of the object as a paramers but the andoid developer need to pass that list as json list array , now when i pass the list as the model that i have made for the web apllication then i receive the list as null , and when i pass the same request after making another model (json to c#)with same fileds and datatypes i get the list of the model. 

now when i pass above request  as parameter then i get the null in InsertGWMultiListmodel , SO  i have coverted this request into Json2charpe converted and pass that model as a paramerter .

i am calling the api by passing GWDetailList as paramerter and i am getting the list , so my question is I dont want to creat two model for the same purpose & why i not getting the list of object in InsertGWMultiList. 

1. [Route("GroundWater/InsertGWDetails")]    
2.       public HttpResponseMessage InsertGWMultiDetails([FromBody] GWDetailList model)    
3.       {    
4.           try    
5.           {    
6.     
7.              
8.           }    
9.           catch (Exception ex)    
10.           {    
11.               throw ex;    
12.           }    
13.       }