Was it a 2024 1040V? A 1040V was probably for 2023. The 2024 form might not have been ready yet. I would check with the IRS and see what year they applied it to. You should have sent it with a 1040ES form for an estimated payment. I think the only spot you can enter it would be as an Estimated payment and hope the IRS matches it up.
To enter Federal or State Estimated Taxes Paid, including a state estimated payment made in January for the prior year, go to
Federal on left or at top (Personal for Home & Business)
Deductions and Credits
Then scroll way down to Estimates and Other Taxes Paid
Estimated Taxes - click the start button
Federal Estimated payments should be on 1040 line 26.