The California Service Center (CSC) does not accept inquiries from the general public via email.?All inquiries must be submitted to the National Customer Service Center by calling 1-800-375-5283.?The National Customer Service Center will route your inquiry to the appropriate USCIS?District Office or Service Center, and will track your inquiry to a final resolution. If you've received a transfer notice regarding your case please inform the National Customer Service Center at the time you submit your inquiry. The National Customer Service is available Monday through Friday, 8:00 AM to 5:00 PM, PST.