Turn your instant pot on to saute and drizzle in the olive oil and then toss in the sausage, onion, garlic, red pepper, green pepper, and celery. Saute it for 5 - 8 minutes until it has softened a bit. Then remove it from the pot.
Add the butter into the pot and let it melt, then pour in the flour and use a rubber spatula or whisk to mix it. Let it cook, stirring constantly until the mixture turns a golden caramel color.
Pour in the chicken, crushed tomato, stock, creole seasoning, and bay leaves. And a pinch of salt and pepper. Give it all a stir together then place the lid on and make sure it is securely fitted. Turn the instant pot on to manually select high pressure and let it cook for 15 minutes.
Release the steam and then carefully remove the lid. Add in the prawns, stir it together. Place the instant pot back onto saute mode and let the prawns cook for 5 minutes.
Taste your dish and see if you need to add more salt and pepper. Remove the bay leaves and serve as you like it.