Once you have access to a candidate's Quickin profile, you will be able to edit information regarding their resume. To do this, simply access a specific candidate and click on the "edit profile" option, see:

When clicking on this option, Quickin will even present options below that were possibly not being displayed as there was no data filled in.

If you have created the candidate's profile manually, and have not added a file with the candidate's CV, simply click on the edit profile option and scroll down to the last part, you will be able to find the option to add the file.