You go too long without eating, then ask your stomach to handle a full meal.
Lower appetite can make skipping meals feel easy. Then dinner becomes the first real meal of the day, and your stomach has to handle more food at once than it is ready for.
That can lead to heaviness, nausea, bloating, or the feeling that food is just sitting there. The issue is not that you need huge meals. It is that your gut often does better with a steadier rhythm.
Try smaller, more predictable eating moments instead of saving most of the day for one heavier meal.