Msal Service Exception in Active directory code

Hi,

I am getting below exception:

MsalServiceException: A configuration issue is preventing authentication - check the error message from the server for details.You can modify the configuration in the application registration portal. See https://aka.ms/msal-net-invalid-client for details. Original exception: AADSTS7000218: The request body must contain the following parameter: 'client_assertion' or 'client_secret'.
Trace ID: f684a1b7-0969-4a54-a480-92fb41183000
Correlation ID: eadd8b53-98d9-4709-ad76-7cf2ed6b7c0c
Timestamp: 2020-01-29 20:19:51Z

Also code is in below link and also issue is raised there :

https://gist.github.com/kalyankrishna1/0a6ea6d00a09f7ae81c89960e1038d79

Please help.