The $1,400 was the Recovery Rebate Credit which the IRS removed from your tax return.
Apparently you answered No when asked if you received the 3rd stimulus payment in 2021 of $1,400. The IRS has records which show you were sent the 3rd stimulus payment so they removed the credit.
Go to your tax account to see if the 3rd stimulus payment is listed - https://www.irs.gov/payments/your-online-account
