When you completed the Moving Expense section (T1-M), you need to enter your "Net Eligible Income earned at your new location". Your moving expenses cannot exceed the amount which you have entered here, and only if you entered an amount which exceeds this would TurboTax allow a claim higher than the eligible amount.

Net Eligible Income is explained in this CRA link. https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-re...

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