The link is secured and can only be used once. Open the last link and use the "Request a new email" button to obtain a new link via email.
Does this button not appear? Then the document has reached its expiry date or there were too many wrong attempts. Please contact the file manager of the office directly and not via the mail from "firstname.lastname@example.org".
Does this error message appear from the first attempt and do you use a security system that scans the content of your e-mails? Then the one time link are read by the security system and have already been used. Add connective.eu to the trusted domains or ask your IT administrator.