Outlook won't sync when not connected to wifi

[PFSP]

I believe this happened at the last update. But my phone will now no longer retrieve emails from my POP account when not connected to wifi. So at home it synchs and gets the email with no issues. But when on cellular it does not sync either automatically or manually. When I press the sync button it tries t sync and just returns "last updated x hours ago"

Is anyone else having this issue?
Does anyone know a fix?

thanks