Set your Instant Pot to Saute. While its heating up, chop your celery, carrots, onion, and garlic. Season chicken in salt and pepper, then lightly coat in flour.
Cook down vegetables in olive oil in the instant pot for about 3 minutes. then add chicken; stir occasionally until saute cycle is complete. Pour in chicken broth, water. Add salt pepper, chopped thyme and bay leaf.
In a large bowl, mix flour, baking powder, salt and pepper. cut in butter until it's evenly incorporated, then stir in milk. It should be a thick dough. If too liquidy add more flour, if it seems too dry add a little more milk.
Drop in medium, to large spoonful sized chunks of dough into the Instant Pot. Close the lid, and set to Pressure Cook for 5 minutes. Let the pressure release naturally (aka do nothing, and wait till the floating valve drops). This will take a while. Once done, you're ready to serve. Enjoy!
For added flavor, use skin-on chicken, and remove the skin before serving.