Providing feedback for a meal item can be done within the Lark app itself.
Log your food item in the conversation. When Lark asks you what you ate, she responds instantly with feedback and tips about your meal. Next to Lark's interpretation, there will be an "i" in a circle symbol.
By tapping the "i", you can send us feedback to look into the meal that you logged so that we can update our food database if you think it has been mis-logged. Lark is constantly updating her food logs everyday to provide smarter meal tracking.