There seems to be a recent feature in the local Outlook app that auto-populates a Teams Meeting link when scheduling a new calendar meeting.
A quick workaround for this would be to click on "Scheduling Assistant" to add attendees, instead of clicking on the button "Invite Attendees".
In Scheduling Assistant, click on "Add Attendees" at the bottom to search for people and rooms. When everyone has been added, click the "Send" button, or click on "Appointment" to return to the normal meeting view.
If you do not use Teams or do not need the option of Teams, you can disable the Teams add-in:
- In the Outlook desktop app, choose File and then Options.
- Select the Add-ins tab of Outlook Options dialog box.
- Confirm that "Microsoft Teams Meeting Add-in for Microsoft Office" is listed in the Active Application Add-ins list
- At the bottom of the window, next to Manage (COM Add-ins), Click Go…
- Deselect the checkbox next to Microsoft Teams Meeting Add-in for Microsoft Office.
- Click Ok
- Restart Outlook.
Or, try turning off the auto-add option in OWA:
- Sign in to https://outlook.office.com/mail/
- Click on the Gear in the upper-right corner (Settings)
- On the leftside column, select Calendar > Events and Invitations
- Uncheck the option "Add online meeting to all meetings"
- Or, select Zoom instead of Teams
- Click Save