What type of grass? And where do you live?

I live in Edmonton, Alberta Canada and I'm not sure it's a mixed breed Kentucky Bluegrass and something else.

Define, watering properly and topsoil.
That sod could have been stressed or even dieing when it was put down. It may also be nitrogen burn or weed preventer became the straw that broke the camel's back.
Was some type of fertilizer put down on top or underneath the sod?

If you are watering 3x per day for about 5 minutes each time, then you are watering properly. Recently someone wrote in who was told to water 3x per day 45 minutes each time. I wrote back to say it was probably 3x per day 4 to 5 minutes each time. Big difference.

Do you know how long the sod sat on the pallet before putting it on the ground?

And I'm confused about the topsoil, too. Why did you need topsoil at all?

Did the grass turned green after watering or it just gave up? I am in similar situation so checking :)