Sender of notification email not editable

I have Mail Poet installed in a Multisite WordPress install with 14 different sites running.

I am trying to change the Sender Of Notification email but on 4 of the 14 sites the sender of notification is not input box and is instead just plain text. What could cause this.

Here is a link to an example of what I mean. On the top its just plain text showing the email address(I Photoshopped out the full email). While on the bottom it has an input box for the email address

Example

https://wordpress.org/plugins/wysija-newsletters/