您好 Low_235,
Regarding this error message “You're missing out! Ask your admin to enable Microsoft Teams”, first office 365 user must have assign license of Microsoft Teams from office 365 Admin Center. After that user can sign in to Microsoft Teams. If you have not access permission of Office 365 Admin Center, for further assistant please contact your Office 365 Admin for assigning license of Microsoft Teams.
Following are steps and screenshot about Team access permission from office 365 Admin Center.
Go to Office 365 Admin Center> Users> Active users> select the user, choose Licenses and apps >scroll down to Apps Segment > tick Microsoft Teams for that selected user.
Sincerely,
Anesu | Microsoft Community Moderator
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hello ,
Please note that our team will respond to your enquiry in English, you can post your response in your native language and we will translate it in-house. Thanks for your understanding.
Regarding this error message "You missed it! Ask your admin to enable Microsoft Teams", the first office 365 user must assign a Microsoft Teams license from the office 365 admin center. After that, users can log into Microsoft Teams. If you don't have access to the Office 365 admin center, please contact your Office 365 administrator for more help assigning licenses for Microsoft Teams. Here are the steps and screenshots for Teams access in the Office 365 admin center.
Go to Office 365 admin center > Users > Active users > select users, select Licenses & Applications > scroll down to the application segment > tick for selected users
Sincerely,
Anesu | Microsoft Community Moderator