Responsive menu exists but doesn't appear

[RDmagic]

Hi.
I’m almost done with a new webpage. Nearly everything works fine.
But: I still have the great problem, that if I change size of the browser to keep a look to the responsive menu the menu appears only a very short time and then disappears behind the slider. And I have no idea why this happens and how I can change this behaviour. The URL to the webpage I would send to you privately.
Thanks for any help.

Ticket