Preheat the air fryer to 400°F.
In a small bowl, mix together the olive oil, garlic powder, paprika, salt, and black pepper.
Pat the salmon fillets dry with paper towels and place them on a large piece of aluminum foil.
Brush the olive oil mixture evenly over the salmon fillets.
Place lemon slices on top of each fillet.
Fold the aluminum foil around the salmon to create a sealed packet, making sure it is tightly closed to prevent steam from escaping.
Place the foil packet in the air fryer basket and cook for 10-12 minutes, depending on the thickness of the fillets, until the salmon is cooked through and flakes easily with a fork.
Carefully remove the foil packet from the air fryer and let it rest for a few minutes before opening.
Garnish with fresh parsley if desired and serve.