Joomla 5.2.2 with JEvents 3.6.83 - Site Template not work when open Calendar

Hi,
did build a Link in Mainmenu
If click to the link the Site Template: Helix Ultimate 2.2.1 is gone.
How to setup that JEvents useres the SiteTemplate ?

PHP Version : 8.3.14

MySQL Version : 10.5.19-MariaDB-0+deb11u2

Server Information : x86_64

*** CONFIG NOT SAVED*** 

Fix jQuery? : Yes

Load JEvents Bootstrap CSS? : Yes

Max Input Vars ? : 5000

Club code set? : No  

User Agent : Mozilla/5.0 (X11; Linux x86_64; rv:128.0) Gecko/20100101 Firefox/128.0  

Joomla : 5.2.2

component_com_jevents : 3.6.83

module_mod_jevents_cal : 3.6.83

module_mod_jevents_custom : 3.6.83

module_mod_jevents_filter : 3.6.83

module_mod_jevents_latest : 3.6.83

module_mod_jevents_legend : 3.6.83

module_mod_jevents_switchview : 3.6.83

plugin_actionlog_jevents : 3.6.83 (not enabled)

plugin_content_jevents : 3.6.83

plugin_finder_jevents : 3.6.83

plugin_installer_jeventsinstaller : 3.6.83

plugin_search_eventsearch : 3.6.83

plugin_system_gwejson : 3.6.83