repair package did not arrive

After repairing my iPhone at Apple it was shipped by Apple to the address I mentioned but the package did not arrive. The shipment is done by Fedex and I do not know what to do. Who can help me

this is the email that i receive from Apple :

our product has been repaired and we're sending it back to you. You should receive it in about two business days.

Model: IPHONE 7

Repair ID: D2*****465

Courier: FedEx

Tracking number: **** (active within 24 hours)

Shipping address:

MASSACHUSETTS

UNITED STATES