Facebook Pixel : advanced matching value for [em] is missing

Hi,

I installed the facebook pixel. But in the chrome extension “Facebook Pixel Helper”, I keep having those warnings for Page view and Microdata :

  • The advanced matching value for [em] is missing, or is formatted incorrectly. Learn more

Anyone knows what I should do ?

https://preview.webflow.com/preview/yukido?preview=1c3991f1a843547e12e9003e4cf5c92b