Turn Instant Pot to SAUTE setting, and when display reads HOT, add the olive oil, onions and corn, and cook until slightly brown
Hit CANCEL to turn heat off, and pour in a little chicken broth, and stir bottom of pot to deglaze and remove any brown bits
Place chicken breasts in bottom of pot. Season with sea salt, garlic, cumin and pepper
Add green chiles, diced tomatoes, remaining chicken broth and enchilada sauce
Place lid on Instant Pot, turn knob to sealing position, and hit PRESSURE COOK, or manual, for 10 minutes
After 10 minutes, allow a 5 minute natural release, then turn knob to venting for a quick release. After pin drops, open lid, and remove chicken to shred
Return chicken to soup, stir in ½ cup heavy cream, and serve immediately