We usually see this with packages going to Canada.
Chicago is usually the last scan before it enters Canada. If you look at the tracking history you will notice this message.
__Your item departed our USPS facility in CHICAGO IL INTERNATIONAL DISTRIBUTION CENTER on April 16\, 2019 at 11:09 am. The item is currently in transit to the destination.__
Canada Post technically does not have to scan the package once it enters into Canada which means it would just keep showing the last scan location (Chicago). Canada post usually does scan the packages but it is also not uncommon for them not to scan the package. If they decided not to scan it for whatever reason it does not mean there is anything wrong with it either.