Happens quite often. I wouldn’t worry. Sometimes it seems it’s sitting in limbo someplace when it is actually moving. Dec 30th? I’m sure any day now you will get a update with a USPS tracking number and only a few more days to wait. I have had stuff from Banggood, Gearbest, Ali, and Fastech just show up with no tracking info updated until it got to my house, then it showed delivered. Seems somewhere between 2 weeks and 10 weeks is the norm for me. 3 weeks being a average and almost 3 months being the longest.
I am assuming you ordered from Intl Outdoor. Last order I got from them was 7 weeks from order to my door. I don’t know how the govt shutdown has affected US customs though. I’m not up on how all of that works.