A problem with adding a new child(appendChild)

Im totally new to JS , i wanted to add a new element by using .appendChild , but something is wrong. In console i can’t even see a new span that shoudl be there.

Welcome to the GitHub community, @Fuscal ! We’re happy you’re here. You are more likely to get a useful response if you are posting your question(s) in the applicable category and are explicit about what your project entails–giving a few more details might help someone give you a nudge in the right direction. I’ve gone ahead and moved it for you. Good luck!