ok this is very confusing if you select YES for
Will you claim employment expenses for working at home due to COVID-19 for income on this T4?
On the T4 data page, the home office expenses under the normal T2200 process do not apply to your deduction.
I would say make sure this is NO (at least that seems to make work for my case.
I am not sure under what circumstances that would be YES. Probably if you are using the new method for home office expenses.