Whenever a customer fails to submit to a registration service any documents, compensation, or fees requested in writing by the registration service, the registration service shall return all documents pertaining to the incomplete transaction, including the department receipt evidencing any fees paid, within 60 days after the request was sent to the customer, to the last known address of the customer, by registered mail.
Source:
Section 11406.5, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH§ionNum=11406.5..