why isn't the pre header showing in my sent email

[William_A]

Hello @Mari_Isomaki ,

Your email program can only show so much in its inbox wording preview. If the combination of your organization name and subject line are too long, or the size of your email program's wording preview is too short, the preheader may be cut off or unable to be seen altogether. Also keep in mind that if you have a longer subject line, a preheader shouldn't be necessary for enhancing your email's header, as it's generally recommended to only use 5-7 words for a subject line to begin with. 

For more info on optimizing your subject line