Press SAUTE button on the instant pot. Add olive oil to the pot.
Once the oil is hot, arrange chicken breast in the pot in a single layer. Brown the chicken by searing for 3-4 minutes per side. Remove the chicken from the pot
Add onions and garlic to the pot and saute for 3-4 minutes until the onions start to brown.
Add carrots, potatoes, and corn and cook for 2-3 minutes.
Now add broth, oregano, cumin powder, turmeric powder, chili powder, bay leaf, salt, and pepper powder, and stir until combined.
Place the chicken breasts back into the pot and close the lid.
Set the valve to the sealing position. Press CANCEL and then press PRESSURE COOK. Set the timer to 8 minutes at high pressure.
Once the timer goes off, let the pressure release naturally for 10 minutes. Release the remaining pressure manually and open the lid. Discard the bay leaf and take out the chicken breasts on a chopping board.
Shred the chicken using a fork.
Add the shredded chicken back to the pot. Press SAUTE button once again. Add pasta noodles and lime juice to the pot. Cook for 6-7 minutes or until the noodles soften.
Transfer the soup to serving bowls. Garnish with chopped scallion (green onions) and serve hot.