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Just to let you know, you can only do these things if you are an account administrator or above.
To change a user's role, login to your Administrator account and go to the home page. Click on the settings icon 
and select the "Account" option.
Go to the "People" tab.
The "People" tab lists users created for the account. Find the name of the user whose role you want to change. On the right side of the user's name, click the settings button 
.
This shows the profile of the user.
In the "Role" menu, select a role for the user.
Standard users can record calls and see recorded messages. Administrators have extra permissions such as managing user accounts. For more information about Administrators, see "Account Administrator".
When you have updated the user's role, save changes.