What Might Be Causing Persistent, Pink, Raised Bumps On My Temples That Harden, Crust, And Repeat Every Few Weeks Without Pain Or Itching?

I am a 74 year old male, 5 7 , 120 lbs. I have a continuous appearance of pink bumps just slightly raised on both of my temples. The outbreak hardens over 2 to 3 weeks and becomes crusty until I wind up picking the crust off and then starts the process over again. There is no pain or itching. It seems to very slowly climb up my temples.