Colombian here. I have the exact same issue. I applied in early April as well. Received the IRCC letter giving me 60 days to provide the document. The Canadian Embassy does not reply to webforms, email, or phone calls. Losing my nerves here. If you get any update, please let me know.
@Miss bee besides submitting all proof of payment, emails, and PCC application, anything else you can advice us to do? In my case, the third party sent the PCC to the Canadian Embassy in my city, back on April 12. That's all I know, as the Embassy is irresponsive and they are supposed to take only 1 to 4 weeks to forward the PCC to IRCC.
Thanks in advance,