DIAGNOSIS You are overloading the basket or not using the dual-layer rack correctly. The preset programs assume proper air circulation.
FIX Do not stack food. Use a single layer. For larger batches, use the included dual-layer rack. Place the rack in the basket, put food on both layers. This elevates the lower layer so hot air can circulate underneath it. Shake the basket or turn items halfway through cooking.
IF THAT DIDN'T WORK The heating element may be underperforming due to a fault, but this is rare. First, manually set the temperature 10-20 degrees C higher than the preset and monitor results.
HEADS UP Pat dry any wet food (like thawed fries or marinated meat) with a paper towel before cooking. Excess surface moisture creates steam, which leads to sogginess.