Nokia 7.2 is a premium looking midrange device that was announced at IFA2019 last September, together with Nokia 6.2. The update for Nokia 7.2, that includes the March security patch as well, is 1.57GB in size and you can check the availability for your unit by going to Settings->System->System Update. Keep in mind that the update won’t be available for all users at the same time, so some patience is required. Usually most users get it in a period of a week.
The 7.2 joins the list of seven Nokia Android smartphones that already received Android 10. These smartphones are Nokia 7.1, Nokia 8.1, Nokia 9 PureView, Nokia 7 plus, Nokia 6.1 Plus, Nokia 6.1 and Nokia 2.2. Rest of the portfolio should get the update before July 2020.