Sometimes it happens, I've had a package get flagged like that and went to pick it up, no issues. Try calling customer service first to see whats up, they might get it un-fucked for you. But first, contact the vendor and ask whats up.
The only time I've seen this was when all my mail had to be put on hold at the post office due to mail box being gone until a new one was put up. While the mail hold was in place, this is what shows up on ID when the pack is at the PO and ready for pick up. I picked up a few packs like this with no issues.
If you did not place your mail on hold yourself, either PO fucked up a scan or something like that most likely. If it doesn't resolve itself you can try what other poster said and contact the vendor first, then possibly the PO.