Instant Pot Corn and Potato Chowder

Name: Instant Pot Corn and Potato Chowder
Ingredients: 3 Tbsp. butter; 1/2 white onion (diced); 2 cloves garlic (minced); 2 cups red potatoes* (diced); 2 stalks celery (chopped); 3 carrots (peeled and chopped); 15 white mushrooms (thinly sliced); 1 small green bell pepper (seeded, halved and diced); 3 cups vegetable stock; 1 can great northern white beans ((Save liquid)); 1 can yellow corn ((Save liquid)); 2.5 cups whole milk; 3 Tbsp. corn starch; 2 tsp. sage, fresh; 2 tsp. rosemary, fresh (chopped); salt and pepper to taste