Hi @HarshD ,
I used a similar method on my side to configure Flow, which can update PromotedState.
The only difference with you is to change the double quotes to single quotes in Body, as below:
Please take a try again.
I also tested it with double quotes, and it can also update the value of PromotedState.
We can demote or unpromote news using following list view extension
Fill out a quick form to claim your user group badge now!
We've given our badges an overhaul and also added some brand new ones!
Learn how to build the business apps that you need.
Find out where you can attend!
Watch & learn from the Power Automate Community Video Gallery!