In B2B assign user to the user group?

Summary:

After creating user group under manage user group how to assign the particular user group to a user so that user can access article in my knowledge page?

Content (required):

Created a user group as 'user group for test' and assign this user group while creating an article but this article was not accessibly for any user so now created a new role for a particular user and added the 'user group for test' under Data security policy and also user under Users tab but still the user with the role is not able to access the article in My knowledge Page. For better understanding of issue, I have attached a document with screenshot and example. Please Check.