Please help me to see what I need to do. I mailed my renew EAD package to USCIS Texas center, but used the certification mail, and the mail address is PO box. Now USPS status shows that the mail was not delieved and may redeliver or be returned in 15 days. Should I mail a new package now or just wait to see if it will be redelived or returned? Will it be returned definitely? Thanks!