If you have integrated the widget in your website, and your website has a floating menu or element, that stay in a fixed position when you scroll the page and appear to "float" on top of the page as you scroll, you should add the code below to your booking page before the <script> widget in the HTML element, to ensure that the widget will correctly show on the page without being hidden by the floating menu:
<script type="text/javascript">
bookeo_topOffset=50;
</script>
50 is the value in pixel and you may have to input a larger number depending on the hight of your floating menu/element.
Therefore the full script you have to add to the HTML source code of your web page should be similar to
<script type="text/javascript">
bookeo_topOffset=50;
</script>
<script type="text/javascript" src="https://bookeo.com/widget.js?a=12345ABCDEFG"></script>