I'm somewhat new to Power Automate and I've been banging my head on this seemingly simple scenario:
User enters a new record. The record contains a People column. A single user name is entered in that field.
On submit, I want Power Automate to get the Department name for that user, and populate a text field called Department.
I've successfully used "Get My Profile" and extracted the Department name and forwarded it in an email.
But for the life of me, I cannot figure out how to get the string to populate the Department field on the record.
The most obvious method leaves the field blank:

And I've attempted to do it using a JSON trick I found online:

But always the same result - the flow runs without error and the Department field remains blank.
Help!