DIAGNOSIS You're likely not using enough liquid, or you're using a thickener like flour/cornstarch directly in the pot before pressurizing. The Crock-Pot Express needs a minimum liquid amount to come to pressure and avoid scorching.
FIX For this 6-quart model, you need at least 1 cup of thin liquid (water, broth, etc.) for most recipes. Never add thickeners directly to the pot at the start. If a recipe calls for them, stir them in after pressure cooking, using the Sauté function to thicken.
IF THAT DIDN'T WORK The Sauté function might be running too hot. Try using less time on Sauté to brown ingredients, or add your liquid sooner to stop the cooking before switching to a pressure mode.
HEADS UP Dairy (like milk or cream) and starchy ingredients (like pasta or rice) can sink and burn if not suspended in enough liquid. Always add those last, after pressure cooking.