Getting cold sores on my lip that popup out of nowhere haven't had a cold or done anything to hurt it what could cause this and how to stop it?

Oral herpes: Oral herpes outbreaks typically occur randomly, but usually no more often than 3-4 times a year. Although they can be triggered by other infections (hence the names cold sore, fever blister) or injury (e.g. sunburn), most outbreaks occur randomly, with no obvious trigger. Treatment can speed healing or help prevent outbreaks. See doctor to confirm diagnosis and discusss prevention and treatment.