To amend your 2016 tax return follow the instructions in the Link below:
https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
To add your mortgage interest follow these steps:
How To Enter a Mortgage 1098
• Open your tax return in Turbotax
• Select the Federal Taxes tab at the top of your screen
• Select Deductions and Credits
• Click I'll choose what I work on
• Scroll down the page to the first section titled Your Home
• Select Show More at the right
• Select Start to the right of Mortgage Interest, Refinancing, and Insurance
• Go through this section and enter your 1098 from your main home.
