1099-R Increased my tax due

I did a backdoor Roth IRA contribution $6000 for 2021 on April 2022. In the same year around June 2022 I did a back door Roth Contribution of $6000. I got my 1099-R form with a value of $12,000, under wages & income section when I enter my 1099-R (uploaded the PDF) it increased my taxes by $1400. This should not happen since my back door Roth IRA is after tax deduction. Can some experts help me here?