Customizer Not working (javascript error)

Hello everyone,

I have a problem with the theme’s customizer.
Indeed, when I want to customize an item (like “Home Main Content Area” for example), the customizer doesn’t move, and i can read on the console a javascript error : “Uncaught TypeError: t.onChangeSectionExpanded is not a function“.

I already empty the browser’s cache, and i tried to customize my website with another theme, and the customizer works.
Furthermore, i tried to customize another wordpress’s website with the the theme Fitness-Hub, and the customizer still doesn’t work (but works with another theme).
Finally, i tried to disable all my plugins, and activate them one by one, but without success.

So, can you help me to find where the error comes from ? Thanks you for your answer.