Modify team member name after original login

[JohnLenz]

My team members installed teams and accepted the member invite; however, the name I see is their eMail address (login). How can I modify the name from email to real names?

[#2]

Hi, the display name is populated from Azure AD so how does it look there? If you are hybrid with on-premise AD the change would have to be made there and synced with AAD Connect.

[#3]

@ChristianBergstrom 

Members are not part of domain. External participants. How to change, if at all?

[#4]

@JohnLenz In that case no (AFAIK.) But for guest users you can update the information in Azure AD.