Add the carrots, celery, and minced garlic. Sauté for about 3 minutes. Stir in salt, black pepper, smoked paprika, chili powder, dried thyme, and dried oregano.
Stir in the lentils and pour in the diced tomatoes, crushed tomatoes, and vegetable broth. Add the bay leaves. Close the lid, seal the Instant Pot, and set to high pressure for 15 minutes.
Stir in the lemon juice and add the baby spinach. Let the greens wilt for about 2 minutes. If the soup needs more liquid, add some broth to reach your desired consistency.