This looks to be a template issue. In the layout for your template, it is not rendering the component.
I verified this by going into your Template's style > Global settings area. In the After Head setting, I temporarily pasted the following at the end:
<div class="row">
<jdoc:include type="component" style="xhtml"/>
</div>
This renders the component. When I saved a reloaded, the login form was shown at the top of the page as expected since we're in the Users component.
You will need to contact your template company Joomlart to resolve the issue.
-Melissa