How to split one text file into multiple text files according to text content?

Hi, Yoichi.

Your data.txt file:

I tried your sample file & is working.

But when I replace with my actual text by replacing ur data.txt, there are no split files.
Mine actual data.txt file:


Is it because of the wording “page 1” & “page 2” has effect the run? Because your sample file do not have “page 1” & “page 2”