Baby has Bad rash again | TMI

Moms this is the second time my daughter has a rash this bad. And this time I don't know what else to apply. What could cause this type of rash ? It itches her badly she's had it for a little over a week now. Her apt is on Friday. She hasn't tried any new foods I haven't either (she's breastfeed she's 12 months)

She was on Huggies snug and dry and I switched to Pampers cruisers to see if that was it but she still has it.

*I've applied destin, organic coconut oil, hand expressed my milk onto the rash, and Boudreaux maximum strength & nothing has worked.