If you arrive at a U.S. port of entry and do not have all your signed required documents, have not paid the I-901 SEVIS Fee on your current Form I-20 or have a SEVIS status issue, a CBP officer may issue you a Form I-515A, “Notice to Student or Exchange Visitor.” The Form I-515A admits you to the United States for 30 days while you obtain and submit the proper documentation to SEVP.
If you receive a Form I-515A "Notice to Student or Exchange Visitor" it is very important that you send your response to SEVP within 30 days. If you don't, it will negatively affect your F-1 status and you may be required to depart the United States.
1.) Contact the ISO immediately if you receive an I-515A so that we can help you prepare your documents
2.) The form is a checklist that describes exactly what is missing or incomplete and tells you what you must do
2.)Send the required documentation to the address given on the I-515A before your 30 days are up (before the "admit until" date on your I-94). As long as you do this, your visa status will not be violated:
Per DHS, your SEVIS record status will terminate if DHS does not receive the requested documentation by the I-94 expiration date. As a result, your legal status in the U.S. will end.