Excuse me, when brushing your teeth, why does it hurt when your lips touch toothpaste?

Maybe your gums are too soft or you brush your teeth too hard.

Avoid eating some irritating foods, especially those that get angry, because the gums get angry easily.

The choice of toothbrush is also very important. Use a toothbrush that is too hard.

If your lips crack easily, just add more water. Don't always add your lips with your tongue, so your lips will crack more easily. Apply lip balm every day and before going to bed. Because lips lose water most easily at night.