I finished my taxes and everything checks out but it shows I owe $ b/c not taking into account amount I already paid when I extended in april

To enter, change or delete a payment made with an extension request (Federal, State, Local) -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Deductions and Credits
• Click on I'll choose what I work on (if shown)
• Scroll down to Estimates and Other Taxes Paid
• On Other Income Taxes, click on the start or update button

On the next screen select the type of extension payment made and click on the start or update button

The payment made with the extension request will be included on your tax return as a tax payment, Form 1040 Line 70, Form 1040A Line 46.

Or enter federal extension payment in the Search box located in the upper right of the program screen.  Click on Jump to federal extension payment

Enter what you paid when you filed the extension, under the Deductions & Credits tab in the Estimates & Other Taxes Paid section. Confirm it's not already entered their first though.