Probably because before you told TurboTax that you DID receive a stimulus payment, TurboTax had added the first and second calculated payment to your refund. When you said you did receive it already, TurboTax removed it from your refund.
You are not being taxed on it - you just do not get the same payment twice.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
