Zoom- I cannot hear the teacher and all participants on my labtop

Hi jcative! Welcome to Zoom Community!  😀  Some of the reasons that it happen are probably the audio selected was changed to another one. i.e. You are using the computer audio and suddenly shifted to a bluetooth headset. When this happens, first thing i would do is to test my audio if the settings are correct and if it is assigned to the proper input/output. 

Here's a video on how to test your audio. 🎵

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