charitable deduction from California state tax refund

California allows filers to donate to various charitable causes by reducing their refund. I did this in 2020 when filing my 2019 state tax return.  My 1099-G says I got the full refund without the reduction, so should I enter the reduction as a charitable donation? Two questions: (1) where in TurboTax do I enter this?  (2) I already have more than $300 deductions for donations, so would it make any difference?