product variations not found

Hello, the Smart Woocommerce Search plugin was running fine with variable products for almost 2 months but suddenly – since a week – our product variations are not shown in the search result anymore. Now only simple products are found.
In the product settings the parent products in our shop are hidden from search resulls and shop page and only the product varaitions are set to ‘visible’. When I change that the product variations are displayed correctly but also the parent product is shown.

We have a redirect for countries outside the EU, but with this address you should be able to see the website:
Website: https://borowski-glas.de/shop/?no_redirect
Best regards, Barbara

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