Just like in a saucepan, some preparations, especially ones containing milk or cream, can stick to the bottom.
Try to use ingredients that are at room temperature, make sure you keep to the temperatures indicated in the recipes, and for recipes where you have encountered this problem in the past, try reducing the temperature and increasing the speed and cooking time.
A sudden change in temperature causes milk to burn more easily, keep the temperature below 100°C, and try using smaller amounts.