There are many different reasons why you can have any problems with tracking your parcels with provided tracking number. First of all you need to understand that your tracking number will not be available for tracking immediately. It can take up to 14 days to receive any information about your package since you get tracking number. Of course, generally it take a couple of hours or days. Anyway, keep in mind that some delay is possible too.
We've assumed above that you're using official site of your postal service to retrieve information about your tracking number. But quite often you need to use third party web sites to check tracking numbers. In this case such sites can not recognize tracking numbers of your postal service. It is possible if a package was sent with some small and cheap postal service.
Finally, it is possible that you've been provided with wrong tracking number. Generally it happens when for cheap purchases from China. The problem is that a seller should pay a couple of dollars for a tracking number. He simply can't do that for low price (up to $10) items.
So, it is good idea to check two points once you received tracking number from another person: 1. Ask him which exactly site can be used to check this tracking number. 2. Check correctness of the tracking number for international parcels. Contact a sender of the package if there is no any information about your parcel when two weeks period is over.
It is good idea to install package tracking extension. It will notify you when information about your parcel will became available.
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