What's the difference between по and в? Both are used for "on" (given day)
"по пятницам наша фирма не работает"?
The word "firm" is given later in the course.
Anything wrong with: По-пятницам в нашей компании не работается? Thank you.
It roughly means that the atmosphere in your company does not favour work on Fridays.
"по-пятницам" is a spelling mistake.