Here are Canada Revenue Agency links with information regarding Expenses Tax Info Centre

CRA  Eligibility criteria - Temporary flat rate method 

Note: For the flat rate method to be activated in TurboTax Online, you enter your T4 and scroll down to the bottom where you will be asked: Will you claim employment expenses for working at home due to COVID-19 for income on this T4? NEW!  You will then click on Employment Expenses found lower in the menu on the left side of the screen to then answer yes on the right screen. On the Employment Expenses Profile page, check the option: I didn't receive either form from my employer. On the next screen Check the flat rate method and enter the number of days you worked from home.

You have now used the flat rate method to claim employment expenses.

Thank you for using TurboTax.

I am using the desktop standard version.  

I get to the Employment expenses page, click mine and my wifes name, hit continue

Then I have to click 'I didn't receive ....', then click the two check boxes (or it says I am not eligible)

Then I enter the days at home on the T777S

But when I try to file it says I need to complete a TP 64.3 General Employment conditions to make the form eligible.  If I try to click past it I cannot Netfile.  I have only tried on one of the Quebec forms but the Error appears on all 4 family members.  If I click fix it just tells me to submit the TP 64.3.  

So I am stuck and cannot file.  Advice?  Or should I expect a program update soon?

I'm having the same issue as @kitmonster. 
I entered my amount of days for the flat rate and all looks good. I'm able to Netfile with Canada without any issues but then when I try to file for QC, it's giving me an error and telling me to submit the TP 64.3 General Employment form. Is this a bug? Am I entering something wrong? 

Please advise. 

Thanks 

Check this thread that says its at the Gov end and to be fixed on the 4th march.  We will see.

Solved: Error on Quebec form when claiming fixed rate Covi... (intuit.ca)