Blanks on form-

[Abygail 0]

I just checked on our I-751 package that I sent overnight via USPS and got this:

"Notice Left - We attempted to deliver your item at 10:59 AM on March 13, 2007 in MESQUITE, TX 75185 and a notice was left. A second delivery attempt will be made. If unsuccessful, we will hold it for five business days and then it will be returned to the sender. Information, if available, is updated every evening. Please check again later."

Is this maybe because it's a PO Box and I should have checked the box to waive signature??? Should I try contacting the USPS and have them return the package to me and not wait 5 business days?

Anybody have input on the postal service? Think I should try to have the package returned if they can't deliver on the 2nd attempt, or will the service center pick it up at the post office?

Well, I'm trying to get through to their local post office, since the 800# told me they'd be holding express mail there for PO boxes - maybe I can just have them return it to me?