Display posts with the same ACF field content in query loop

Sorry if I’m repeating myself, but unfortunately I couldn’t find a suitable topic for this question.

I have a template on the page that I have defined as a landing page template under conditions for a post type.

Everything works great, except for the similar posts query loop.

There, I would like to display only the posts, including the current post, that have the same content in an ACF field (text). Unfortunately, it doesn’t quite work. Posts are displayed, but unfortunately not with the same content.

What I have already done:

Loop type: Posts

Post type is selected

And then Meta:

Key: sem_reihe

Value: {acf_sem_reihe}

Equal, also tried Like

Char

Thank you for helping