The error message indicates that you need to add the state, author, email & created_at columns header. You can leave the column value blank but the headers are required for the reviews to be successfully imported.
You can also attach your import file here, we can help you with direct import.
What should I do, when I try to import the reviews from Google sheets I am getting the following error:
Missing state, author, email, and created_at columns. Please provide both review source and .csv file with right headers.