We have seen a number of USPS shipments get delayed without updates, sometime for weeks, only to suddenly show up later in the system without explanation.
Obviously our current pandemic isn't helping the situation but there have been reports of packages not getting scanned and sitting at a postal facility for days, even weeks, at a time before eventually moving on to the next stage as though nothing had happened.
Unfortunately all of this is out of our hands. While we can use the same tracking system that the customer has access to, we don't get any more information than the little that is supplied by the online tracking tools.
We can only file a lost package claim 45-90 days after the shipment was made. So for the first month and a half we're basically locked out of the process.
At this point we would suggest paying the extra money to have your order shipped via UPS if you are not comfortable potentially having your order take some time-off on its journey to you.