Time series data group by date

Hi I’m using self hosted Grafana v9 to visualize some of my website metrics. In one panel I want to show how many singin does my website have perday. Iam using myslq plugin and my time column is created_at. I created the panel but results are not grouped per day. this is my panel image

and here is my mysql query

  count(session_id) AS "session_id"
FROM session_user
ORDER BY $__timeGroup(created_at,$__interval)

how can I group my result per day

Try $__timeGroupAlias(created_at, 1d),

No it says db query error: query failed - please inspect Grafana server log for details