I have a cron job (*/10 9-21 * * *) I want to run it every day for 10 minutes interval that start from morning 9am and stop at 9pm. But it was not runs as expect. The issue is it is still running after 9pm.

I would like the cron job to run for 10 minutes every day from 9am to 9pm. It will start at 9am in the morning and end at 9pm at night. After this, it will start again the next day at 9am. This sequence will continue every day.