Exact same output - pg_stat_statements

Hi, Whenever I am running the below query on one of my Azure PostgreSQL PaaS instances I am getting exact same output. I feel it shows old information but as far as i know pg_stat_statements only shows current information and not past right ? It may be a bug? 

SELECT dbid,queryid,substring(query, 1, 50) AS short_query,
          round(total_time::numeric, 2) AS total_time,
          calls,
          round(mean_time::numeric, 2) AS mean,
          round((100 * total_time / sum(total_time::numeric) OVER ())::numeric, 2) AS percentage_cpu
FROM  pg_stat_statements
ORDER BY total_time DESC
LIMIT 20;

I have erased the query text from the screenshot below. but Please look at the rest of the columns which are exactly the same. How it is possible ?