What platform are you using ? Check with Italian app, or zoom or teams, may be it could be a camera issues in your laptop

If you are using a Mac, you can turn on PhotoBooth, and it will show your image back to you, as if in a mirror. On any platform, you can go to Google Meet, New Meeting, Instant Meeting, and it will show you image back to you, as if in a mirror. This will confirm that your camera is working, powered on, and not blocked or muted by your laptop itself. If that works, but someone on a video call can only hear you and not see you, it gets complicated. It's possible that you could have blocked your camera in your video calling tool. Just as you can mute your microphone, you can usually block your camera; there's usually a little camera button and it may have a line across it if you've blocked it. If the internet connection isn't good, your calling tool may automatically block video in order to save bandwidth. You should suspect this if your audio isn't clear, especially if it stutters or has gaps in it.

You may be able to go into an old lesson page, scroll to the bottom and look for the iTalki classroom button that says "Enter Classroom." You should be able to test your equipment there. Good luck!