Please check if the Smart Pen sensor is clean, if the product is exposed to direct sunlight, if the Smart Pen is being held the right way, or if the light is off.
Allowable Recognition Angle
Within the Notes App, please check that each stroke of the Smart Pen is mirrored on screen. Do not close the app while the sync pop up is open.
Check the percentage of transferred data in the settings and be sure that it is 100%.
Sometimes the data is there but there are delays with the sync. Please tap on the upper right corner featuring the pen icon for an update or go back to the front cover of your notebook for an update.