Same as here, which got deleted: https://webcache.googleusercontent.com/search?q=cache:jiXK75xcHWQJ:https://turbotax.community.intuit...

Through trial and error, I figured the telephone field for the payroll analyst was required by the SW. Intuit, a little more "guidance" with regards to required and optional field in forms would be nice.

Same issue here, turbotax has almost no support but after many attempts the provincial returns finally transmitted after completing the "unnecessary" TP64.3 form. Fill all fields and in 3.1 put "yes" and all else"no", unless you actually do have employment expenses other than just claiming the basic covid amount. Wish this company would have some actual human  support - better chance of reaching the pope!

Thanks for your hint. It really helped me. But every fields must be filed to work...

Me too I tried several times and it only worked when I completed all of the fields. In some areas I wrote "form not necessary". 

Remplir toute les cases oui ou non,  sur les lignes vierges inscrire "aucun" si vous avez rien à inscrire et au bas de la page remplir  la ligne titre et fonction et la date.  Voilà et ça marche