Chances is that the operator who packed your phone and sim card didn't realize the SIM chip fell off the card and packaged it as "new".
If you are using an existing line, just transfer the old sim into your new phone (provide it still fits).
If you are using a new phone, just take the SIM card to a Fido store and ask them to issue a new one for you.
Keep in mind the SIM card number is printed on the physical chip card that you insert into your phone as well as the plastic holder (in your photo). Even without the chip card, you can still update the SIM number online by using the number printed on your physical card (it should start with 8930 XXXX XXXX XXXX XXXX). That's why when you replace the sim card, make sure you destroy your old sim card chip and the holder.
Happy New Year and Welcome to the Community!
Sorry to hear you're missing the nano-SIM portion. Is it possible that portion of the SIM got knocked out and is loose in the box?
If you are concerned others might start using your services, you can report your device as lost or stolen via your My Account --> Usage & Services --> Report lost or stolen device (under Quick actions, near bottom of page). I understand your actual device might not have been stolen, but reporting it would put a halt on any usage of your services.
You can either go to a Fido Store to purchase a new SIM card or contact customer service to order another one. In addition, they can also be contacted via Live Chat, Facebook, or Twitter. Those methods can be accessed via the contact page posted above.
Normally, you would be able to update your SIM card via your My Account (see here). However, you would need to have customer service update your SIM card since you no longer have your old SIM card number. You may need to update your SIM card in store with identification.
Hope this helps 😀