Baby has a weird rash...HELP 😭

Niaa • Mummy to two boys || 🇿🇼 x 🇬🇧

I’m a new mum & my son is 4 weeks old & has this rash. It started last week just on his forehead & now it’s spread on his face & head. Any idea/advice on what’s causing it & how to get rid of it?