I have embedded the Flodesk code for my opt-in newsletter and it looks very good on the desktop and is working however on the mobile half of the form is UNDER the header. What do I do about this?
Hi @dear-golden 
this is often a z-index issue cause by sticky header settings.
Either disable the sticky header, or fix the themes CSS and possibly javascript to account for the new popup.
If you need this theme repaired then contact me for services.
Contact info in forum signature below 
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ALWAYS please provide context, examples: store url, theme name, post url(s) , or any further detail in ALL correspondence.