explain the requirements and causes that led to changing the subject of vocative discourse in Quran after the migration to madina​

The differences between the two were said to be that the Meccan surahs dealt with core issues of belief, whereas the Medinan verses included the “legislative verses” of the Qur'an.

The Medinan surahs are those supposed revelations that occurred after the move. Meccan surahs are typically shorter than Medinan surahs, with relatively short verses (āyāt), and mostly come near the end of the Qur'an. (As a general rule, the chapters of the Qur'an are ordered from longest to shortest.)

number 2 is your answer.

you answers peoples questions and if you submit anything like   a question you dont know the answer to some else will answer   you question hope this and no you cant write diary