Preheat your air fryer to 375°F (190°C).
Slice the bell peppers, onion, and chicken tenders into strips.
In a bowl, toss the chicken, bell peppers, and onions with olive oil, fajita seasoning, salt, and pepper.
Place the seasoned chicken and veggies in the air fryer basket, spreading them evenly.
Cook for 12-15 minutes, shaking halfway through.
While cooking, warm the flour tortillas in the oven or microwave.
Once done, assemble the fajitas by placing the chicken and veggies on tortillas.
Serve hot with your favorite toppings.