I advise you to not leave Canada until you get your PR card.
Once you receive eCOPR, you become a permanent resident and your temporary work/study permit stops. This means that now, to enter Canada you need either a PR card or permanent resident travel document (PRTD) that can take quite some time to get.
So you can technically travel back BEFORE receiving eCOPR, but you never know when it will arrive so don't try is my advice.
Thanks for your advice
my grandfather has serious illness so I really want to go back home to see him.
I tried to call and can’t reach to the agent.
it’s seem take longer then I thought. Everyone is waiting since Nov.