mobile menu does not collapse

Dear Sirs,

For the website demo.kindercentrummultikids.nl I used your plugin. The plugin is awesome! I only wanted to change the secondary menu and not the head menu. With your plugin I was capable of changing the style of my secondary menu. They are now shown in the orange color as you can see on the website.

But there is an issue which I cannot resolve with your help. When I want to collapse the (left) menu in a mobile or tablet version, it does not collapse. The only time when the left mobile menu collapse is when you delete the plugin. How can I resolve this issue?

I hope to hear soon from you!

Regards,

Luci

https://www.ads-software.com/plugins/megamenu/