Not getting full AZ Tax credit for private school tuition

Hello! I am about done filing my taxes and wanted to give my AZ state tax dollars to a private school as a tax credit but it is only giving me credit for half what I enter to give (I plan to give the payment Friday April 14, 2023).

 

I am filing MFS and taking standard deduction. My employer paid $2,434 to the state and my TT state refund is showing as $862. As I add amounts to the Contributions to Private School Tuition Organizations, my state refund only goes up by half of the amount I enter. If I put in $200, my state refund only goes up by $100 to $962. This means that I can't give without it coming out of my pocket. 

 

Am I missing something here? Does my filing status make it so I can't actually get a tax credit? Thank you!