Un-sticky the header

I’m using Modality with a child theme. What I’m trying to accomplish is that the contact info above my logo bar stays on the screen when I scroll, the logo bar itself will scroll off the screen but the menu will stay on the screen right below the contact info (if you scroll that far or further). When I go into Firefox to use the Inspector, I see that somewhere class=”stuckmenu isstuck” is added to the header-holder div. I’m not sure if this is causing the whole header section to stick but I’m not sure what file is adding this as it is not in the child theme header file (which I copied from the theme and made minor changes to). Can you tell me what I can place where in the child theme so that the large logo bar will scroll but neither the contact info nor the menu will go off the page? Thanks.

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