The Northern Residents deduction is made up of three parts. The part that would cause this error is the Travel component.
Check your travel deduction to ensure the amount you've claimed doesn't exceed the amount of your taxable benefit listed on your T4/T4A.
Here's a link for more details on claiming the travel component of the NR deduction: https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-re...
