Need help with custom visual. I am using Plotly.js

 A custom visual for a grap already exists. I am trying to add a drop down list to select values for X-axis and Y-axis. But when I added HTML for the drop down, the graph disappeared. How do I remediate this issue?

Also, how do I connect grap and the drop down list, so that upon selecting specific values from the drop-down list, the graph changes dynamically?