no date on single blog

Hello WP OnlineSupport,

I have trouble displaying the date of a post to a single blog-post page.
The date is displaying nicely on the page where I put my [blog] shortcode, but not on the blog itself.
Perhaps it’s due the theme, but it won’t work on none of the sites i’ve test it on, and I have no idea how to solve it. I’ve tried everything, from the customizer-settings to CSS/PHP, but nothing seems to work.

Do you have the solution for me?
The theme I use is called: “Flash”.

Thank you kindly in advance!

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