Pemalinks not working without Primary category set

Hi,

I am using “WP All Import” to import data to a custom post type of ‘products’
My products have multiple categories/subcategories.

These all get imported ok, but because no ‘primary category’ is selected, my URL is not created properly. Your documentation suggests if no primary category is selected then it will use the first one. This would be fine, but it’s not doing that for me – maybe because they are added at the same time during csv import?

my permalinks are set up as:
/products/[product_category-term-slug]/[single-products]

But unless I manually go into a post and select a primary category my posts are displayed on a URL like this:
/products/[single-products]

Is there a way forward please?

Thanks in advance