you must prepare, print, sign and mail an amended tax return form 1040X to correct the problem. DO NOT change your original tax return until you start the amended return.
When to check the status of your amended return:
Your amended return will take up to 3 weeks after you mailed it to show up on our system.
Processing it can take up to 16 weeks.
Then you can check the status at:
https://www.irs.gov/filing/individuals/amended-returns-form-1040-x/wheres-my-amended-return-1