See below reply for people who missed attaching all the documents in original application on IRCC webpage. This is reply to my webform query. Hope it helps others.
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Thank you for contacting Immigration, Refugees and Citizenship Canada (IRCC).
If you have an application in process and would like to provide additional document(s) (e.g., letter of explanation, newly renewed passport, etc.), we invite you to:
- Fill out the IRCC Web form available on our website,
- Choose the applicable option located in the drop down menu under the heading Enquiry, and
- Include:
- the information/document(s) in question, and
- a brief description of the situation in the Your enquiry box.
It will be at the responsible office's discretion to determine if the request is approved.
We hope the information provided is helpful in assisting you with your enquiry.