If you able to provide login credentials of your store, we can check and report you soon
Shall you please advise which server are you using for your magento 2 platform?
I have been in similar kind of situation, I have migrated the data from magento 1.9.x to magento 2.2.8 and there was two website in magento, for the default website the product detail page was working fine but for the other website it was not, I was only able to see the blank page where noting rendered in body tag, with that, one thing was sure that it is a layout related issue as magento was unable to load the layout. After spending a day I finally found that in the secondary website layout was updated at product level but it is was also observed that you need to check updated layout in the website>store for the product. The main reason is that code of the layout in magento 1.9 was different to magento 2.x, so try to check layout updates. This may help you in certain conditions only.
Hi @sebest,
you add following code in index.php and now you showing error in product detail page
error_reporting(E_ALL);
ini_set('display_errors', 1);
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