How to do Multi-factor auth with SharePoint-Online CSOM

Question

Using just a password-based authentication, it's easy to authenticate in CSOM from my C# application:

context.Credentials = new SharePointOnlineCredentials(username, password);

But how to authenticate when Multi-factor authentication (MFA) is activated?

 

Since the MFA was activated in the tenant, i get the error: 

 

The sign-in name or password does not match one in the Microsoft account system

Microsoft.SharePoint.Client.Idcrl.IdcrlAuth.GetServiceToken

 

Is there any way?

 

I´ve read about using APP PAssword, but the new password created  doesn´t work from C# code

 

Thanks.