Here you can watch in case of non-delivery of your shipment via the form in your tracking number that was sent to you in your confirmation email when dispatching your order to your email. Through this form you can watch these types of shipments: 

• BX - insured package ( eg: BX123123123CZ )
• BA - recommended package ( eg: BA123123123CZ )
• BO - Business package (eg: BO123123123CZ )
• CS and CV - Recommended package abroad (eg: CS123123123CZ ,
  CV123123123CZ ) 

(Track your shipment via this form can be usually after a couple of hours after delivery tracking number to your email, so it is good to wait for tracking the shipment usually the next business day). 

You can track your shipment on the website of the Czech Post