Diaper Rash..

My daughter has had a rash on her bottom for like a week now, my SO went and got diapers and even tho they were huggies they felt different so I went and got another pack of the ones I've always used. We've noticed she can only use pampers or huggies and I prefer huggies because she pees thru the pampers but this rash isn't going away. I've put Destin and a&d. Its not bothering her. Any ideas if it could be something else, most likely from those diapers... Thank you :)