The note mentions Deven gave his dad stickers. These are very important.

Examine the bubbles on the note carefully.

The bubbles are the same size as the stickers.

Cover up each bubble with a sticker. Be precise.

To decrypt this note, cover up all the "bubbles" with the circular stickers Deven left his dad. Once the bubbles are covered up, you can see the hidden message:

code red hes meeting a reporter tomorrow what should i do

(Note that "report" and "er" are in separate words. Combine them to form the word "reporter").