Marinate the chicken with black pepper, salt, and olive oil.
Preheat the Air Fryer to 200°C until the heater light turns off. This takes about 3 minutes.
Place the chicken in the Air Fryer and cook for 10 minutes.
Flip the chicken and cook for another 10 minutes. Remove.
Dice the cucumber, bell peppers, and onion into small cubes.
Slice the chicken and toss with the diced vegetables.
Heat the pita bread in the Air Fryer at 140°C for 3 minutes. Cut the bread in half and open it gently, as it tears easily.
Place the chicken and vegetables inside the bread.
Serve with Thousand Island dressing.