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Your active phone line(s) will appear in the bottom left corner of the App. If you have multiple lines, they are labeled as “L1”, “L2”, etc:
Ensure you have an audio device setup that you want to use for calls, typically a headset. Note there are 3 different settings. Ringer and Alerts is for inbound calls, chat messages, meeting reminders, etc. Speaker is for any in-call or meeting audio, and Microphone is for your outbound(mic) setting.
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