Hi,
this happen because your template apply the CSS rule "display:flex" (line 6273 in file /templates/jsn_voyage/css/template.css) to the box that contain login form block and social login block.

To fix it you can simply add the following CSS rule to your template:

.login{display:block}

To add this code you can see docs about your template at https://www.joomlashine.com/help-center/getting-started/joomlashine-templates/add-custom-css.html