If you have already NETFILED your income tax return, you will need to submit an adjustment request. Please see the following FAQ for instructions on how to submit an adjustment request, https://turbotax.community.intuit.ca/community/tax-return-amendment/help/i-have-filed-my-tax-return-can-i-still-make-changes/00/873608.
You can also access TurboTax Live Assist and Review using the following link, https://turbotax.community.intuit.ca/community/navigating-turbotax/help/i-m-using-turbotax-live-assist-review-how-do-i-talk-to-a-tax-expert/00/873764.