To enter line 22900 Repayment :

1. Sign in to your Tax return. 
2. In Turbotax, from the left sidebar, go to Income>drop down the "Employment Expenses ". 
3. Click "Yes" on Employment Expenses page.
4. Check the box "T2200 - Declaration of Conditions of Employment" on Employee expenses profile. 
5. Check the box "Other Employment Expenses" > Continue.
6. On the Other Employment Expenses screen is a box in the first section that says "Other Expenses". Make your entry here and it will be deducted on Line 22900 as per Canada Revenue Agency Information - Line 22900 Other Employment Expenses

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