If your extension payment from 4868 line 7 did not automatically show up on 1040 you need to enter it. So make sure it's not already there before you enter it! If your extension payment is more than the tax due you should get a refund on 1040 line 35a.
For 2024 Federal Extension payments should be on schedule 3 line 10. And go to 1040 line 31.
You can type estimates paid in the search box at the top of your return and click Find and it will give you a link to Jump To the screen where you enter Extension Payments.
To enter the amount you paid with an extension (including state extension) go to
Federal Taxes (or Personal Tab for desktop H&B version)
Deductions and Credits
Then scroll way down to Estimates and Other Taxes Paid
Other Income Taxes - Click the Start or Update button
Next page second section Payments with Extension
Either Visit All or Click Start or Update by the extension you paid
If your tax return shows a tax due on 1040 line 37 you can pick you will mail a check instead of entering your bank account.
Check to see if you entered the payment you made when you requested the extension.
When you requested your extension you were supposed to pay your estimated tax due. Did you enter the payment you made into your tax return?
Go to Federal>Deductions and Credits>Estimates and Other Taxes Paid>Other Income Taxes