In a small bowl, stir together 2 tablespoons of oil, 2½ teaspoons salt, ½ teaspoon pepper, the cinnamon, cumin, paprika and coriander. In a medium bowl, toss the chicken with 1 tablespoon of the spice paste. On a 6-quart Instant Pot, select More/High Sauté. Add the remaining 2 tablespoons oil and heat until shimmering. Add the onion and 1 teaspoon salt, then cook, stirring occasionally, until softened, about 6 minutes. Add the garlic, ginger and the remaining spice paste. Cook, stirring constantly, until fragrant, 30 to 60 seconds. Stir in 2½ cups water, scraping up any browned bits. Add the tomatoes with their juice, the squash and chicken; stir, then distribute the ingredients in an even layer.