Not getting access token

Not getting access token

I am coding in C# .Net core 6. I have installed the SDK (ZOHOCRMSDK-2.1). I have this code in program.cs:

  1. var logger = new Logger.Builder().Build();

  3. UserSignature user = new UserSignature("user@email.xxx");

  5. Com.Zoho.Crm.API.Dc.DataCenter.Environment environment = USDataCenter.SANDBOX;

  7. Token token = new OAuthToken.Builder()
  8.     .ClientId("1234567890")
  9.     .ClientSecret("2345678901")
  10.     .RefreshToken("3456789012")
  11.     .Build();

  13. TokenStore tokenStore = new FileStore("C:\\TokenStore\\sdktoken.txt");

  15. tokenStore.SaveToken(user, token);

  17. SDKConfig config = new SDKConfig.Builder().AutoRefreshFields(false).PickListValidation(false).Build();

  19. new SDKInitializer.Builder()
  20.     .User(user)
  21.     .Environment(environment)
  22.     .Token(token)
  23.     .Store(tokenStore)
  24.     .SDKConfig(config)
  25.     //.ResourcePath(resourcePath)
  26.     .Logger(logger)
  27.     .Initialize();

I added a controller / call to retrieve all Modules (as a test)

  1.     [ApiController]
  2.     [Route("[controller]")]
  3.     public class ModulesController : ZohoBaseController
  4.     {
  5.         private HttpResponseMessage _response;
  6.         private string _rtnData = string.Empty;

  8.         private readonly JsonSerializerSettings _jsonSettings = new JsonSerializerSettings {
  9.             ContractResolver = new CamelCasePropertyNamesContractResolver(),
  10.             Formatting = Formatting.Indented
  11.         };

  13.         [HttpGet(Name = "ModuleList")]
  14.         public HttpResponseMessage List()
  15.         {
  16.             //Get instance of ModulesOperations Class
  17.             ModulesOperations moduleOperations = new ModulesOperations();
  18.             HeaderMap headerInstance = new HeaderMap();
  19.             DateTimeOffset ifModifiedSince = new DateTimeOffset(new DateTime(2020, 05, 15, 12, 0, 0, DateTimeKind.Local));
  20.             headerInstance.Add(ModulesOperations.GetModulesHeader.IF_MODIFIED_SINCE, ifModifiedSince);
  21. //Call GetModules method that takes headerInstance as parameters
  22.             APIResponse<ResponseHandler> response = moduleOperations.GetModules(headerInstance);


  25.             // Serialise the return data
  26.             _rtnData = JsonConvert.SerializeObject(response, _jsonSettings);

  28.             //_response = Request.CreateResponse(HttpStatusCode.OK);
  29.             _response = new HttpResponseMessage(HttpStatusCode.OK);

  31.             _response.Content = new StringContent(_rtnData, Encoding.UTF8, "application/json");
  32.             return _response;
  33.         }
  34.     }

But this fails with this at "moduleOperations.GetModules(headerInstance)":
  1. Com.Zoho.API.Exception.SDKException
  2.   HResult=0x80131500
  3.   Message=Input string was not in a correct format.
  4.   Source=ZOHOCRMSDK-2.1
  5.   StackTrace:
  6.    at Com.Zoho.Crm.API.Util.CommonAPIHandler.APICall[T](Type className, String encodeType)
  7.    at Com.Zoho.Crm.API.Modules.ModulesOperations.GetModules(HeaderMap headerInstance)
  8.    at KervPlatformZoho.Controllers.ModulesController.List() in C:\...\Controllers\ModulesController.cs:line 33
  9.    at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.SyncObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
  10.    at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeActionMethodAsync()
  11.    at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
  12.    at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeNextActionFilterAsync()

  14.   This exception was originally thrown at this call stack:
  15.     [External Code]

  17. Inner Exception 1:
  18. FormatException: Input string was not in a correct format.

I have a record in the TokenStore (file) but it is missing access_token, grant_token, expiry_time and redirect_url.

I created a "Self Client", generated a code and used Postman to "Generate Access Token and Refresh Token". I entered the Refresh Token in the code above.

So - what am I missing?