Set Instant Pot to saute mode. Add olive oil, poblano pepper, onion, garlic, carrot, and celery and cook for 2-3 minutes or until soft. Then add cumin, salt, broth/stock, tomatoes and bay leaf.
Add chicken to the Instant Pot. covering entirely with broth/tomato mixture.
Close lid and be sure valve is sealed. Set to Manual high pressure / pressure cooking for 10 minutes. It will take about 8 minutes for the Instant Pot to reach high pressure, then it will cook for 10 minutes.
When timer goes off, let sit for 1-2 minutes. Then set to quick pressure release to vent steam.
Remove lid and remove bay leaf and discard. Remove chicken to shred (use an electric mixer or two forks to shred). Return to Instant Pot and mix well with soup.
Add corn and beans, and stir well.
Serve in bowls and add your favorite toppings.