The item you just added is unavailable. Please select another product or variant.
You do not have a link list with a handle set to shop-by-series-1, or you do and it's empty.
Go ahead and create a link list called Shop by Series on your Navigation page and populate that link list with links that point to collections, to see collections listed here.
Make sure the link list also has a handle set to shop-by-series-1.
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