If you find that an accordion or tab element on your product page is not clickable and the contents of the dropdown are not revealed, this might be related to your theme.
If you are using the Porto theme, check the feature called ‘Skeleton Screens.’
‘Skeleton Screens’ are blank pages on your website that will continuously be populated with content or media, such as text, images, and videos once they are available.
To make the accordion or tab element work again on your product page, you have to disable the Skeleton Screens feature on the Porto theme. Just go to Porto > Theme Options > General > Show Skeleton Screens.