Can you confirm which phone# you tried calling agent irccHere is what my experience was to have this resolved. i created a webform with the uci / application number / full name and attached the signed oath form explaining its over 5 business days and I am still waiting for my e-certificate. Also IRCC agent suggested me to send signed oath form from a different email address also as its not mandatory to send the signed oath form from the same email address that we received ceremony invitation. i did both of these and yesterday morning around 11 am I received email from IRCC in response to my webform created at 6 AM saying my request was approved and the signed oath form was added to the file. Then I called IRCC agent and they confirm they have my signed oath from now on my file and asked me to wait for 1 hour and check and after 1 hour I was able to download the certificate.
note: when I called IRCC agent they shared they had 2 signed oath forms from me and one is from the different email Id I sent and the other is from oath form and they confirmed they did not get any signed oath form from my actual email that I sent the signed oath form after the oath ceremony and also resent again late last week and Monday also and I have no idea why none of those made it to my profile.