Create an account at the CICC website ( https://www.canada.ca/en/immigration-refugees-citizenship/services/application/account.html ) and link using either the UCI, Application # or applicant details. I tried with the applicant details as the UCI and application number was not matching any documents. Also, at the bottom, where it asks for number of people, make sure you add the PA, dependents (if any) and the sponsor and co-signer (if any).Can someone teach me how to link the application to GCkey? Thanks in advance.
Eg; in my case, it was my father-in-law (PA), his wife (dependent), my wife (sponsor) and myself (co-signer). So total was 4. Hope this helps.