Able to login from AD Namespace but not with Flex authentication

[Mfg]

Hello There,

I am trying to access CA 11.0.5 environment where i have configured 2 authentications.
1. AD
2. Flex

Using SDK:
1. When i try to login with AD, i am able to login and run the script to get info from CS.
2. When i try to login from Flex namespace, I get following error:

Error:    at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall)
   at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
   at cognosdotnet_10_2.contentManagerService1.logon(xmlEncodedXML credentials, searchPathSingleObject[] roles)
   at CogLicenses.CognosSA..ctor(String serverHost, String serverPort, String userNamespace, String userName, String userPassword) in C:\Users\Admin\Documents\Visual Studio 2017\Projects\Cognos\Cognos\CognosSA.cs:line 150

CM-REQ-4342 An error occurred with the client.



does anybody came across such issue and have any suggestions ?

any help will be appreciated. Thanks in advance.