I believe I have replied to your question in the other thread, but I will reply it again here. I think it’s better to keep the discussion over here too.
Could you please tell me the version of ACF you are using? If you are using ACF PRO (version 5), please take a look at this page: https://www.advancedcustomfields.com/resources/using-acf_form-to-create-a-new-post/. If you are using ACF free (version 4), please take a look at this page: https://www.advancedcustomfields.com/resources/using-acf_form-to-create-a-new-post/?version=4.
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