Want to remove Mobile Menu and need reset

Hi, I’ve installed the free WP Mobile Menu and played around a little bit. But it doesn’t work as I’ve expected, so I want to remove it. But when I deactivate the plugin, the menu changes on my webpage remain! How can I return to the native mobile menu or reset the modifications…?! in a previous post a function “reset to default” was mentioned, but unfortunately i can’t find it either…

Thanks in advance!

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