Cube your chicken and add to your IP along with your bbq sauce and water or chicken broth (optional add now would be: 1/2 cup chopped onion if you want and 3 tbsp soy sauce)
Stir so chicken pieces are coated well.
Put lid on and close steam valve. Turn your Instant Pot on pressure, high, for 4 minutes.
When it beeps do a quick release and carefully lift the lid. Turn IP to saute.
If you want to thicken the sauce add 1 tbsp cornstarch in small bowl with some hot bbq sauce from pot in with it and whisk together until smooth. Add back into pot and stir.
Add marmelade, stir and allow mixture to bubble for about 2 minutes, stir.