
Locate the Style tab of the section > Shape Divider setting > edit or disable the Top and Bottom divider:

Please check these guides for further information:
Guide to Vamtam Elementor Builder

To hide the shape divider, add the code below to Customize > Additional CSS
.elementor-widget-posts .elementor-post .elementor-post__thumbnail .vamtam-shape {
display: none !important;
}
VamTam Elementor Themes: How to add custom CSS / PHP code or modify the theme code