Content Not Placing Correctly Into Existing Text Frame with Split Paragraphs

Your frame is already threaded. You can see the arrow in the inport on the left, and the arrow on the outport on the right. 

So there's already a promise to another text frame to allow text to flow from that frame into that frame. 

You'd have to break the relationship with the prior threaded text frame, with only the text frame selected and nothing loaded in the placeholder cursor. 

Double click the inport and outports to remove the threading. 

Then you can flow the text into that frame. 

If you have multiple frames to unthread, there's scripts in the scripting folder User section that can Break the text frames (there's 2 of them, not sure which one is right for this instance). 

It does mot work because the frame/story has content. You can only fill empty frames/stories.