Cassiopeia dropdown menu and module problem

Hi, I have a website under construction, Joomla 5.1.2 with a Casiopeia child template.
I wanted to make a drop-down menu on the front and MobileMenu Pro on mobile devices.
Unfortunately, for some reason, when I select the 'collapsible dropdown' option in the 'main menu' module, the hamburger menu does not appear in the mobile view.

CK module version 1.6.4

Please help me solve the problem.

Regards, Gregory

Hi
Please try to use the menu position "top fixed" and let me know if this works
CEd

Thank you for your reply, but unfortunately this change did not improve the module's functionality.

Please give me another suggestion.

ok, please give me the url of your page so that I can check
and why do you want to use this specific layout ?

Ok, the address of the page is under construction: cedrowa.eu/surwin/

Breakpoint is on 990px

Currently, the menu only shows the native hamburger menu from Casiopeia.

ok it seems that Mobile Menu CK is not loaded at all in your page
please go in your menu module ID 87 >> mobile menu ck tab >> enable mobile menu >> is it on YES ?