It looks like you’ve switched to the Impulse theme on your store from your post here. Are you still thinking about using the Symmetry theme?
If you are, as this is a third-party theme developed by third-party developers, this would be outside our scope of support and I would recommend reaching out directly to the third-party developers, Clean Canvas. Here is their contact form.
Have you tried reaching out to Clean Canvas directly about limiting the quantity on your product page? If you have, what did they say?
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