Bad rash on five month old cheeks

Do you guys have an idea what might be causing this I've tried everything from Neosporin to A&D Ointment to even rash cream and nothing is helping or subsiding it he doesn't cry it doesn't bother him but it is bothering me and my husband and we have no idea why this is happening it's been going on two and a half weeks already he breastfeed and bottle-feed but does not sit in his milk if you guys have any recommendations on products I could give a try please let me know thank you so much