Diaper rash

So my little girl has went 8 months not ever getting a rash but now all the sudden I can’t seem to get this one stubborn rash the popped up about two weeks ago away .I change her diaper after like 1 pee it’s never really full and have tried desitin but it’s not working. I also let her hair out when changing her diaper and bath her every other day and am thinking maybe I have to bath her every day ? Any tips how to help or remedies you use on your little ones ?