Hello,
Please check now. The issue is related to the module you are using. When the module is published in the header position, it does not work properly — not only with our template, but also with the Joomla Cassiopeia template. You can verify this from your end as well.
I have made some code changes in the following file to fix the issue temporarily:
JRoot/modules/mod_jt_login/tmpl/default.php
Since this is a third-party module and does not belong to us, we recommend contacting the module provider for further clarification and a permanent solution.
We appreciate your patience and understanding.