Leviticus 25:29 why is a walled dwelling in a city does not follow yovel but a house in a village not surrounded by walls does?

This is based upon the natural affinity and connection that farmers feel for their ancestral inheritance. Where even if someone had no choice but to sell that "heirloom" and family plot, it was probably done unwillingly, so it returns to that original ownership in that 50th Jubilee year, and he can return to live with his family and tribe. On the other hand, when one sells their home in a city and moves elsewhere even after a year, he already gets used to his new surroundings, and is not "connected" that much to his previous location.