Hi @ceekayello,
The dropdowns on https://japparelhk.com work on desktop and mobile in my browser:


.
The http://ceekayello.com mobile dropdowns work, as you said:

The desktop dropdowns do not display for me either. I noticed that http://ceekayello.com uses the Autoptimize plugin: https://ww.wp.xz.cn/plugins/autoptimize/. http://japparelhk.com does not use this plugin.
Could you please try disabling the Autoptimize plugin and checking whether the dropdowns work after that?