Hi Kate!
We've recently updated how sender information works in Ontraport. When you select a user or user relationship in the Send from dropdown, the system automatically pulls the sender name, email, and reply-to address from that user's profile.
If you need more control, you can choose the Custom option instead. That option lets you manually set the sender name, email, and reply-to address individually.
This update is currently rolling out to all accounts over the next few days, so if you don't see it yet, it'll be live in your account soon.
You can learn more here.