Add parameter to RequestBody in ASP.Net

Hi! Where is my mistake? Its not working now. 

request.AddParameter("application/json", "{\r\n    \"token\": \"hjjkf5gh36tr2dfg523gfd\",\r\n    \"data\": {\r\n        \"age\": $"{sendToApi.data.age}",\r\n        \"gender\": $"{sendToApi.data.gender}",\r\n        \"sector\": $"{sendToApi.data.sector}",\r\n        \"district\": $"{sendToApi.data.district}",\r\n        \"region\": $"{sendToApi.data.region}",\r\n        \"amount\": $"{sendToApi.data.amount}",\r\n        \"duration\": $"{sendToApi.data.duration}"\r\n    }\r\n}", ParameterType.RequestBody);