Saving seeding data to database in Laravel

I am participating in a Laravel course. The course was supposed to be laravel 8, but it is 30/70 laravel 8, and laravel 5 was outdated and is slowly updated. The problem is saving seeding data to a database (MySQL). I can save Users to the database in the code but cannot save Blogposts Or comments. The blog posts are supposed to be saved with random user IDs from all user tables so that the specific user who made the post would be able to edit the post he made, not the others. Also, comments have the same story, but comments are randomly assigned to posts. Previously it has been tried to save posts to a database using PHP artisan tinker.

Laravel insert default value instead of data sent via request

I’m facing a peculiar issue on my Laravel app that when I insert data to the database, it always inserts the default value instead of the data sent via a post request. So I dd() the value before inserting them into the database and the correct data showing. But on the database, it always inserts the default value in the migration file.