Menu on mobile not collapsing

Hi, I inherited a website which uses Astra theme and have got working beautifully on desktop, but when on mobile or tablet the menu displays as a drop down and won’t collapse back into hamburger button – so it obscures the pictures on the homepage. I just want a simple (sticky) button for mobile.

I’ve researched fixes which include using block themes (where you don’t have to use the CUSTOMIZER settings) and plugins, but I’m happy with most things on my site so don’t want to change/ start again from scratch. I find the customizer settings for menus very complicated and confusing and think I may have altered something that is causing the issue. Can anyone point me in a good direction to resolve this? Thanksyou

David

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