Does lipstick act as a barrier to Wudu, and should previous prayers be redone if the lipstick fades but does not completely disappear with Wudu?

For the ablution (Wudu') to be valid, it is a condition to remove anything that prevents water from reaching the skin. If the color or stain remains in such a way that water can reach the skin and flow over it without adhering, then the ablution is valid. Lipstick should be removed so that no obstructing residue remains that would prevent water from reaching the skin. However, the mere presence of the color does not cause harm.