Receive MethodNotAllowed in v107

I am attempting a POST request in v107 that used to work before v107. See https://stackoverflow.com/questions/70686539/v107-getting-status-code-of-methodnotallowed-on-a-post-request-that-used-to-work for details. As suggested by Alexey there I have re-written some code and now I get an exception with MethodNotAllowed, rather than a response with status - MethodNotAllowed.

To Reproduce Reworked Code:

//constructor
public MerlinServiceBase()
{
    GetCreds();
    _authClient = new RestClient(_authUrl);
    _authClient.Authenticator = new HttpBasicAuthenticator(_authClientId, _authClientSecret);
}

private async System.Threading.Tasks.Task<string> GetAuthTokenAsync()
{
     var request = new RestRequest().AddParameter("grant_type", "client_credentials");
     var response = await _authClient.PostAsync<Dictionary<string, string>>(request);
     return response["access_token"];
}

Expected behavior I expected to get an auth token

Stack trace

System.Net.Http.HttpRequestException
  HResult=0x80131500
  Message=Request failed with status code MethodNotAllowed
  Source=RestSharp
  StackTrace:
   at RestSharp.RestClientExtensions.<PostAsync>d__11`1.MoveNext()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at RentalWebClient.V3.QA.Automation.UI.MerlinServiceBase.<GetAuthTokenAsync>d__10.MoveNext() in C:\Source\OpenTech\Kiosk\Ota.Kiosk.RentalWebClient.V3.QA.Automation\RentalWebClient.V3.QA.Automation.UI\_Merlin API\Merlin_ServiceBase.cs:line 87

  This exception was originally thrown at this call stack:
    [External Code]
    RentalWebClient.V3.QA.Automation.UI.MerlinServiceBase.GetAuthTokenAsync() in Merlin_ServiceBase.cs

Desktop (please complete the following information):

• OS: Windows 10
• .NET Framework 4.7.2

Additional context Please let me know what other details I could add.

[dcdraper]

We use Amazon Cognito with client_credentials: https://docs.aws.amazon.com/cognito/latest/developerguide/token-endpoint.html

I am still trying stuff here and there, learning about and finding my way around the the new and old layouts of the client and response objects. A minor thing I noticed is that Resource is set to “” instead of null on the new RestRequest object, but moving “/token” to there from my base url seemed to not help (or hurt) at all.

[dcdraper]

That fixed it 😃 Thank you so much for spending so much of your valuable time on it, it is appreciated!