Teams join button failing

Dear @Isabella Fernandez,

Please correct me if I’m misunderstanding your scenario. Based on your description, it sounds like you are able to join a Microsoft Teams meeting on one device, but when you open Teams on a second device and select “Add this device”, the meeting does not successfully join on the second device.

Please try the steps below and test each one.

1.Refresh the Teams session on the second device

Teams needs to recognize your session as active in order to offer the device‑handoff options.

1. On your phone, fully close the Teams app (don't just minimize it).
2. Open Teams again.
3. Look at the very top of your "Activity" or "Chat" tab. You should see a  bar that says "Join a meeting in progress" or "You're in a meeting on another device."
4. Tap Join call, and then select "Add this device" from the two options that appear.

2.Manually add the device from the Calendar

If the banner doesn't show up, you can manually trigger the device addition through the calendar:

1. In the mobile app, go to the Calendar tab.
2. Find the meeting you are currently in.
3. Tap Join
4. Teams will realize you are already in the meeting on your PC and will present the choice: "Add this device" or "Transfer to this device." Choose "Add" to keep both active.

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this. Thank you for your patience and understanding. If you have any questions or need further assistance, please feel free to share them in the comments so I can continue to support you. I'm looking forward to your reply.

If the answer is helpful, please click "Accept Answer" and kindly upvote it.

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To join a Teams meeting from a phone and then add another device, use the multi‑device join feature.

1. First, join the meeting from the primary device (for example, the phone) using the normal meeting link or calendar entry.
2. On the second device (for example, a laptop or tablet), open the Teams app while the meeting is in progress.
3. A banner appears near the top of the screen indicating there is an ongoing call or meeting on another device and asking to join it on this one.
4. Select Join.
5. When prompted, choose Add this device (not Transfer to this device).
6. Teams automatically mutes the microphone on the second device to prevent echo. After joining, the camera and mic can be turned on or off as needed, and content can be shared from either device.

If starting from the laptop first, the steps are the same: join on the laptop, then open Teams on the phone, tap the Join the meeting on this device notification, and the phone will be added with mic and speaker muted by default.

References:

• Join a meeting in Microsoft Teams
• Join a Microsoft Teams call on a second device