What’s I’ve found related for this topic in on the site of CBSA:
If you wish to apply for the return of the seized document(s), please complete this form and mail to the address noted on the BSF698 "Notice of Seizure of (a) Travel and/or Identity Document(s)" that was provided when the seizure occurred.
For general inquiries, please contact the Border Information Services line at 1-800-461-9999.
https://www.cbsa-asfc.gc.ca/publications/forms-formulaires/bsf699-eng.html#
If you wish to apply for the return of the seized document(s), please complete this form and mail to the address noted on the BSF698 "Notice of Seizure of (a) Travel and/or Identity Document(s)" that was provided when the seizure occurred.
For general inquiries, please contact the Border Information Services line at 1-800-461-9999.
https://www.cbsa-asfc.gc.ca/publications/forms-formulaires/bsf699-eng.html#