If the microphone is not working in Zoom or other apps on your Dell laptop, you may be able to make it work again using the following steps:
1. Click on the speaker icon in the lower right of the screen.
2. Click on the right arrow that is to the right of the speaker icon.
3. On the bottom of that window, you should see More volume settings. Click on that.
4. Scroll down until you see Advanced. Click on All sound devices.
6. Under General at the top, you should see Audio. If there is a button that says "Allow", click on that.
7. Below that, there is a Test your microphone option. If you click on Start test, it may not work the first time. If not, try it again. If the mic is working, you should see the meter responding to sounds.
8. Test the microphone with the camera app or start a test Zoom session.