Filter doesn’t show all products with attribute. Multisite.

Hi,
We had the filter working well in a multisite of 3 sites, but it has stopped working.
It still works well on the main site https://besttile.co.uk but not on the child sites https://besttile.ie. and https://besttile.boutique
What happens is the filter only shows some of the filter results. It doesn’t show all products that meet the criteria of the filter.
For example, this filter result:
https://www.besttile.ie/product-category/metro/all/?yith_wcan=1&filter_tile-colour=blue&query_type_tile-colour=or
It only shows 6 results, but it should show over 300 results.
This is one example of a product it should show, but does not show:
https://www.besttile.co.uk/product/tahiri-garden-25cm-x-25cm/
If you check the additional information you can see it has ‘Blue’ in the Tile Colour attribute.
The same filter on the main site shows over 300 products.
Can you help us fix it? Do we get priority support if we purchase the pro version?
If there’s anything you need please just let us know. Thank you.
Regards,
David

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