Store leftover instant pot chicken legs in an airtight container in the refrigerator for 3-4 days. For longer-term storage, freeze it in an airtight container or a freezer bag for approximately 3 months. When ready to use, thaw it in the refrigerator. When reheating in the oven, preheat it to 350°F (175°C). Place the chicken on a baking sheet and cover it with foil to prevent drying. Heat for approximately 10-15 minutes or until it's heated through. If using a microwave, arrange the chicken on a microwave-safe plate and loosely cover it with a microwave-safe lid or cover. Reheat in 30-second intervals until it reaches your desired temperature. For an air fryer, set it to 350°F (175°C) and reheat the chicken for 4-5 minutes or until it reaches your desired temperature and crispiness.