Why am I not getting the $2000 child tax credit for all 3 of my children? It's awarding for my 17 year old and 8 year old, but not my 9 year old.

It's giving me the $500 "other dependent" credit, like it is for my child who turned 18. But given that they're a minor, shouldn't I get the full $2000 tax credit like I am for the other 2 children?