How do I enter a 1099 after I've already filled

If you already filed your return and it has been accepted, you need to amend the return to add Form 1099-SSA.

Here are the steps to amend your return:

1. Sign in to you account.
2. Scroll down to Your tax return & documents , select 2019 and then Amend (change) return. 
3. Select Amend using TurboTax Online.
4. follow the instructions, your refund or tax due will change to 0. This is normal on amended returns.

After you start amending the return you can add form 1099-SSA by following the steps below:

 

1. Log in to your account.
2. Go to Federal Taxes.
3. Go to wages and Income.
4. Scroll down to Retirement Plans and Social Security and click show more.
5. Click start next to Social Security (SSA-1099, RRB-1099).

After adding all the forms you will see the instructions to print and mail the return. Amended returns can't be e-filed.