Are other users in the organization having the same issue?
Are you trying to set up the meeting from within the Microsoft Teams desktop client?
If the issue is specific to the MS Teams desktop client, try the following steps to clear the application cache and try again:
Step 1. If Teams is still running, right-click the Teams icon in the taskbar, and then select Quit.
Step 2. Press Win + R to open the Run box. Then type %AppData%\Microsoft\teams in the box and press Enter to run it.
Step 3. In the pop-up File Explorer window, double-click the Cache folder and then delete all files in the folder.
Step 4. Restart Teams.
If clearing the cache doesn't help, please check if Teams is updated to the latest version.
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