Your mic works in the browser but not in Zoom? Here is the fix

Check the app permission

When the Microphone Test shows a moving line, the hardware and browser permission are fine. The problem is almost always one setting inside the call app. On Windows and macOS, each app needs its own microphone access. Open the privacy settings, find Zoom, switch the toggle on, then fully quit and reopen Zoom.

Pick the right input device

Apps remember the last device they used. After plugging in a headset, open the audio settings in Zoom and select that headset manually. The arrow next to the mute button is the fastest place to do it. Choose the headset itself, not Same as System, if the system input is still the laptop mic.