Mark the envelope and the cover letter with the type of submission. For example, Original Submission, Application to Register Permanent Residence or Adjust Status (Form I-485). Mark the envelope and the cover letter with the form number. For example, Form I-129, Form I-360, Form I-485.
You can call the USCIS hotline and request they send you a new receipt.
If you have not received your notice, you may submit a case inquiry with USCIS in the “did not receive notice by mail” category. For example, if you did not receive your approval notice and believe it may have been lost in the mail, you may submit a case inquiry as explained above if you know your receipt number.
If you do not know your receipt number, contact the USCIS Contact Center for help. You can continue to use Informed Delivery to track and manage the delivery of your package.
You should receive a receipt notice within 30 days after filing at a Service Center or 30 days after filing at a Lockbox.
Call the USCIS Contact Center at 1-800-375-5283.