Here’s a tip you’ll probably need. You can quickly turn Teams On/Off at the Org level.

Typically, if the Teams is not enabled at the Org Level, you’ll see this error message

if you click on the Enable Teams button, it’ll take you to this Microsoft Docs page – https://docs.microsoft.com/en-us/MicrosoftTeams/office-365-set-up?WT.mc_id=DX-MVP-5003911

Turn Teams On or Off at Org Level

To skip searching through the Microsoft Documentation on turning Teams On at the Org Level, do the following –

1. Go to the Microsoft 365 Admin Center, then look for Settings, expand it. Then, go to Org settings
   
   
   
2. Now, look for Microsoft Teams in the list of Services. Click on it.
   
   
3. Once the Teams’ Settings open, you can see that you can either enable the Team On or Off for all Users. Also, you can manage Guest Access as well.
   

Check Teams Provisioning Access

Post the above, there might be a few users or new users who might have been Teams provisioned through their licenses.

Here’s how you can check it –

1. Use this link to check if Teams has bee provisioned to the users or not – https://admin.microsoft.com/AdminPortal/Home#/teamsprovisioning
   
   
2. If not assigned yet, make sure you enable Microsoft Teams for the users by going into their Licenses and expanding Apps section.
   
   And then, look for Microsoft Teams
   
   
3. Teams should then be enabled for Users.
   
   

Hope this helps. Here are some more Office 365 / Microsoft 365 Admin / Teams related posts you might want to check –

1. Adaptive Cards for Teams to collect data from users using Power Automate | SharePoint Lists
2. Adding a Canvas PowerApp to Teams
3. Import multiple Users in Office 365
4. Office 365 Admin: Quickly Enable Multi-factor authentication for users
5. Create new Sandbox and copy Production over to it in PowerPlatform Admin Center
6. Restrict User Access to a D365 instance using Security Groups
7. D365 Quick Tip: Audit User Access in Dynamics 365 v9 CRM

Thank you!