Could you please make sure if you put the code inside The Loop? The issue you had probably occurred because you were trying to execute the have_rows() function outside of The Loop. To fix it, you need to pass the post/page ID as the second parameter to the have_rows() function like this:
Where “99” is the post/page ID where the custom field is assigned. This page should give you more idea about it: https://www.advancedcustomfields.com/resources/get_field/.
If that doesn’t help, could you please try to debug the value like the following?
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