When edit file the file shows well but when just read the content of this file, it is truncated

I got a file in the master branch and when I click this file , it shows only 25k lines of this file while in fact it’s over 30k lines.
Only if I click the edit button then will I see the whole 30K lines.

This problem extends to the Azure Data Factory application ,cause I deploy the pipelines in Github, when ADF reads file from github ,it reads a truncated one.

When I asked the Microsoft Azure engineers they suggested me to refer to you for help.If you guys would help, then he would call a teams meeting to solve this problem.

So can you give a hand to help see what is the problem here?