Upgrade from Free to Teams

It sounds like your issue stems from having two separate Teams environments associated with the same email address—one from your previous personal/free Teams setup and the other from your current Business Basic plan. Here are a few possible solutions:

1. Transfer Meeting Ownership (Not Possible Directly)

• Unfortunately, Microsoft Teams does not currently allow the direct transfer of meeting ownership between different accounts.
• Since the meetings were created under the free Teams version, they are still tied to that environment, which is why you can't join them from your Business Basic account.

2. Use the Same Meeting Links

• If the meetings are still valid, you should be able to join them using the original links.
• If clicking the link defaults to the wrong Teams account, try:
  • Copying and pasting the link into a private/incognito browser window.
  • Manually switching to the correct Teams account after clicking the link.

3. Recreate the Meetings in Your Business Account

• If you still have access to your old Teams Free account, open each meeting, copy the details, and recreate them in your Business Basic account.
• If you need to keep the same meeting links, inform attendees of the change and provide them with updated invitations.

4. Merge Calendars for Visibility

• While ownership transfer isn't possible, you can merge calendar views by:
  • Syncing your personal Outlook calendar with your Business account (via calendar sharing).
  • Inviting your Business account as a participant to the meetings, allowing you to join from the Business Basic Teams app.

5. Check if You Can Join via the Web Version

• Sometimes, Microsoft Teams web app handles multiple accounts better than the desktop app. Try joining the meetings via Teams on the web while signed into your Business account.