Facial features never really stop changing completely although for most people the facial features are mostly changed by age 18 to 21.
Facial features change the most from birth to age 18 to 21 years old.
Then as you get older your face will sometimes continue to change some but not as much as it did before you were 18 to 21.
My facial features and face changed quite a bit from age 13 years old to 18 years old.
And I also noticed quite a bit of facial feature change from 18 to 21.
After age 21 my facial features stopped changing as much but I do notice that my facial features are still changing after 8 to 10 years.