I'm claiming 3 dependents under age 17, Why is my Child Tax Credit Total is only $1,611? My AGI fir 2023 is $13,241. Why I don't I get the full $2,000 per child?

I'm Filing Head of Household with 3 dependents under age 17 and AGI $13,241 for 2023; My Child Tax Credit is coming up only $1,611? Why don't I get full $2,000/child tax credit?