TurboTax has created an FAQ link to help you make your amendment. Be aware that the Canada Revenue Agency (CRA) suggests waiting for your Notice of Assessment (NOA) before making any changes as the assessment may have already corrected the amount left out. Please follow the link included below.
I have filed my tax return. Can I still make changes?
The CRA also has a link with information about Change My Return which you can use through your My Account once you have received your NOA.
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