Getting raw json as output in react app in the browser

I am building a blog app using mern stack.To fetch the data from backend i am using axios. For state management i am using react-redux. For the first time i open any page of, it renders correctly. Image below :

And after auto-refresh i am just getting the raw data in the browser. like this :

I am getting this raw json output on every page. (not in the first rendering of the page).