As per CRA- If you receive a lump-sum payment, it appears on your Form T4A, Statement of Pension, Retirement, Annuity and Other Income, or your Form T3, Statement of Trust Income Allocations and Designations.
To fix the error message, you will have to go back to the "Income" section and click on the Slip that was entered and click on "Edit" to view what was entered and in which boxes to make sure they were entered correctly. Once corrected/deleted then click on continue. Then you can return to the "Review" section to make sure that there is no error message and file your return.
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