sub item in menu on mobile devices

I have sub items in my menu (only one level down, see screen capture) but they do not appear on android and iphone.
I saw there were tutorials for other themes for 3rd level sub items. I don’t need to go that far, and only the mobile theme is affected. Plus I would love something easier to implement!
Any hints for a simple solution ?
Thank you !

Hi @sheelf,

I hope you are well today and thanks for posting here.

Could you please share me your site URL where it’s happening so that i can troubleshoot it?

Kind Regards,