Next, in the same pot add onions, celery, and carrots, sauté for few seconds, then add the garlic and cook until the onion softens.
Add the chicken broth along with Italian seasoning, chili flakes, black pepper, lime juice, lime zest, and pasta.
Mix everything and add in the meatballs.
Cancel the Sauté function. Select the Pressure Cook button on High Pressure for 6 minutes. (Make sure the valve is in Sealing position).
Once the pressure cooking cycle is over. Quick release the pressure by manually moving the valve from Sealing to Venting position. Do this gradually at first to avoid soup spewing from the steam release vent.
Open the lid carefully and select the Cancel/Off button.
Serve the soup hot. Garnish with chopped cilantro.