Grease 4 muffin molds with cooking spray. Set aside.
In a bowl, mix together the flour, oats and baking powder.
In another bowl, add the sugar, and butter and beat until creamy.
Then, add in the egg and vanilla extract and beat until well combined.
Add the egg mixture into oat mixture and mix until just combined.
Fold in the raisins.
Place the mixture into the prepared muffin molds evenly.
Slide the Air Fryer Basket inside and adjust the temperature to 355 °F to preheat for 5 minutes.
After preheating, arrange the muffin molds into the Air Fryer Basket in a single layer.
Slide the basket into Air Fryer and set the time for 10 minutes.
After cooking time is finished, remove the muffin molds from Air Fryer and place onto a wire rack to cool for about 10 minutes.
Carefully invert the muffins onto the wire rack to completely cool before serving.