When you filed with TurboTax you filed Form 1040. You should have filed Form 1040-NR (or 1040-NR-EZ). To fix it you have to file an amended return, Form 1040-X, for each year with the correct Form 1040-NR attached. You cannot do this with TurboTax. Download Form 1040-X and its instructions from the following links on the IRS web site. You can easily complete the Form 1040-X by hand. You can use the current version of Form 1040-X for both 2018 and 2019.
Form 1040-X
Instructions for Form 1040-X
Here is what the IRS instructions for Form 1040-X say to do if you filed Form 1040 and you should have filed Form 1040-NR or 1040-NR-EZ instead.
• Enter your name, current address, and social security number (SSN) or individual taxpayer identification number (ITIN) on the front of Form 1040-X.
• Don't enter any other information on page 1. Also, don't complete Parts I or II on page 2 of Form 1040-X.
• Enter in Part III the reason why you are filing Form 1040-X.
• Complete a new Form 1040-NR return (see below).
• Across the top of the new return, write "Amended."
• Attach the new Form 1040-NR return to the back of Form 1040-X.
Since you are a student, you should be able to use Sprintax to prepare your Form 1040-NR (or 1040-NR-EZ) return. TurboTax has a partnership with Sprintax to prepare a 1040-NR federal tax return and corresponding state tax return for certain categories of nonresident aliens. Go to the following link for details and to get started.
Sprintax
IMPORTANT: You have to do this separately for each year. Mail the amended return for each year in a separate envelope. Do not put both years in the same envelope.
An amended return cannot be e-filed. You have to print it and file it by mail. It normally takes the IRS up to 16 weeks to process an amended return. However, the IRS is currently not processing mailed tax returns because of the Covid-19 pandemic. When they start to process them again they will have reduced staff and a huge backlog, so it will be a long time before your amended returns are processed.
Don't file the amended return for 2019 until your original Form 1040 tax return has been accepted and you have received the original refund.
