In case you need to make the sticky header to appear on downwards scroll please follow the steps below:

Step 1: Open the Edit with Elementor > Header Transparent:

Step 2: Open the "Advanced" tab of the Header Section and delete the vamtam-sticky-header vamtam-sticky-header--transparent-header code from the "CSS Classes" field:

You can also watch this video:

Step 3: Next, go to the Style tab of the section and set the header background colour:

Tip: If you'd like to have a transparent-to-solid sticky header, make sure that the "Effects Offset" option is not zero, and that you have added the custom CSS as shown in the video guide:

You can also check this guide: Vamtam Elementor Themes: How to edit the header area?