Pour 1 cup of water into the Instant Pot insert and place the trivet in the pot. Place the beets on the trivet.
Secure the lid and set the pressure release to sealing. Manual(Hi)/Pressure Cook for 15 minutes. Let the pressure release naturally, this will take about 10 minutes. Open the pot and wearing heat-resistant mitts transfer the beets to a plate or cutting board. Let cool. When cool enough to handle, peel the beets and cut them into ½-inch cubes.
In a medium bowl whisk together yogurt and salt. Stir in cucumber.
Add the beets to the raita, stir to combine, and garnish with the mint. Store in an airtight container in the refrigerator for up to 3 days and serve chilled.