Messed up email when sent

Hi,

After updating all my plugins, woocommerce and wordpress, the confimation emails that are send when someone orders a product, are messed up.
In the customizer the template email looks perfectly fine, but when I send it (as a test to myself), it is completely messed up. The layout looks weird, things moved to random places and there is some HTML code visible at random places.

Can anyone please help me?