I have already e-filed both my federal and state (California) return for 2018. Later I found that I missed entering a 1099-B. I made 2 mistakes after I found I there's an error.
- I didn't know how to amend a return in Turbotax at that time, so I immediately modified my return, and that changed my return and refund amount. (I don't think this is the key of my mistakes)
- After googled, I knew that I need to use the built-in amend function to do that, so I did so. Once I started the amending process, I realized that I shouldn't modify the return before I started the amendment. I didn't know how to cancel the amending, so I switched to the forms mode (from the upper-left corner) and manually deleted 1040x (for federal) and schedule x (for California). (I believe this is the key of all the mess I have right now)
After done these steps (I also deleted the 1099B I added in step 1), I thought I've fixed everything, so I started amending my return by using the built-in amendment function. But after I finished my amendment, I only found 1040x in my new federal return/amendment, and there's no schedule x in my new state return.
Let's say I've gotten my return $2000 from federal and $2000 from the state, but I should only get $500 from each because of the missed 1099B. In my new federal return, I have a red $1500 which is correct; but I see a white $500 in my new state return and there's no schedule x. The new state return looks just like a regular return which I believe is wrong.
I tried to redo everything, but I still got the same result. I believe that is because I ever manually deleted the schedule x in the forms mode and that polluted the data file? But how can I fix this?
If you saved a copy of your original return, you should start a new amendment using a fresh copy. If you did not save a copy of your original return, you should re-create your original return (you may need it some day, anyway) and then save the new "original." Make a copy and amend the copy, not the original return.
Here's how to Amend My Return in TurboTax.