Can anyone help

I would say teething rash. My boys looks the same. Is your little one dribbling a lot?

If teething, saliva becomes more acidic. Pop a little bandana bib on and keep saliva dry from around mouth as much as possible and see if that helps. If you have breast milk pop some of that one to the rash. X

My LG has the same. Teething rash from dribbling loads x

My boy gets this when he's been dribbling. I use the my expert midwife dribble barrier after his night time bottle and it normally clears up within a few days. It is expensive but really works!