Dump wild rice, mushroom, vegetable stock, onion, celery, black pepper powder, salt, poultry seasoning, and minced garlic in an inner steel pot in Instant Pot.
Stir well and cover it. Pressure cook it on high pressure for 45 minutes.
In a pan, heat olive oil. Add all-purpose flour, cook it for 2 minutes, stirring continuously. Add coconut milk and stir. Cook it for 2 minutes. Switch off the flame.
Once instant pot beeps, switch off and give a quick release. Now, add prepared roux in a soup. Mix well.