Once you've changed your name, you'll need to notify the Canada Revenue Agency(CRA) of your name change before you file your return.
Make sure you did complete a legal name change from CRA here update your CRA information: Change your name
You also need to change name on your TurboTax Online return. Go to the left side and click on My info - Personal Information
You can either remove your middle name and or edit any related information.
For more information, please click: TurboTax Advising the Canada Revenue Agency of a Name Change
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