Hi @Natalie,
Welcome to the Microsoft Q&A forum.
Thank you for contacting us. We understand that you want to receive Teams call notifications directly through your Bluetooth headset instead of the external speaker. Please follow these steps:
Go to your phone’s Settings: Settings > Sounds and Vibration > Separate App Sound > Audio Device, then select Bluetooth Device.
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 the issue.
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 on this post so I can continue to support you.
I look forward to your response.
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