Header appear twice

Hi! I use intuition theme, but I know the issue does not come from the theme itself but from my coding under wordpress, I think I located it but I don’t know what to code instead.
My website is https://derbyfrance.com/ the main page is perfect but every time you go to another page where there is not any sliders, the header appear instead a second time, instead of not displaying anything.
If I’m not wrong the issue comes from header.php and this part :

<?php }else{ ?>

			<?php $header_image = get_header_image(); if($header_image != ''): ?>
			<img src="<?php echo $header_image; ?>" class="header-image" />
			<?php endif; ?>

What do you think I should write instead?
Thanks in advance for your help