Preheat the air fryer to 350°F (175°C).
Spread mayonnaise on one side of each slice of bread.
Layer the turkey, Swiss cheese, lettuce, and tomato on one slice of bread, then season with salt and pepper.
Top with the second slice of bread, mayo-side down, and press gently to hold everything together.
Place the sandwich in the air fryer basket and cook for about 6-8 minutes, flipping halfway through.
Once the sandwich is golden and the cheese is melted, remove it from the air fryer and let it rest for a minute.
Slice the sandwich in half, serve, and enjoy!