You will need your old SIM from your previous carrier unless your previous carrier is Telus or Koodo which can be done without the old SIM.
If not Telus/Koodo, you need to get a new SIM from them and transfer your old account to the new SIM then contact a CS_Agent to restart the porting process for you.
@Suzanna You need to make sure old providers account is still active and leave old providers sim card in phone to reply YES. To the confirmation text to port . Will send you the porting team number private message as we not allowed to post it here and they can re trigger the port request for you .