Mobile menu does not close automatically

Hello together,

I’ve got a problem with the menu of my site posttraumatische-belastungsstoerung.com (which means “posttraumatic stress disorder” in German). I hope that somebody can help me.

Description of the problem:
-I have a menu item “Traumatherapie München” which contains eight sub items (“Über mich”, “Behandlungsspektrum”, “Therapieverfahren”…)
– All eight sub items lead to the same page but to different topics on that page (anchor links)
– If you click on one of these eight items, the target page opens and the menu dissappears (so until that point everything is fine)
– If you open the menu again and chose another item which leads to contant that is above the current content the menu does not close automatically (which is the problem I would like to fix)
– If you click on an item which leads to contant that is below the current content the menu closes automatically (as it should be)

I hope that I could decribe my problem well. In case of questions don’t hesitate to ask me.

I am very thankful for your help.

Best regards from Munich
Stephan

The page I need help with: [log in to see the link]