There are 2 different types of nappy rashes in broad categories....those due to irritation from the urine and diaper...and those rashes that tend to occur in the nappy areas...It takes a Paed dermatologist to differentiate
Please, allow the diaper area to be exposed to air at times when you are home...don't always cover with diaper...let there be period off fresh air just blow the area. If you do this, most diaper rash will disappear.....
Paediatrician