Diaper rash that won’t go away 😭

My baby boy is 7 weeks old and has had a horrible diaper rash since he was 2 weeks old. I have been to the doctor THREE times for it. She has prescribed magic butt paste from the pharmacy, antibiotic ointment for the sores and a yeast ointment as well. Nothing is working! I have tried everything. I change him every hour, give him diaper free time twice a day , breastmilk baths, many many over the counter diaper creams , I’m even wiping him with just cotton balls and water. These sores are all on the inside between his cheeks. The ones on the outside could dry up and heal for the most part but the ones on the inside have not even healed even a little. I’m wondering if I should try baby powder to try and keep it super dry versus putting all these wet ointments on, but I have heard bad things about baby powder. Also we use Pampers swaddles. Please help 😞

UPDATE: Turns out the magic answer to these sores that have lasted weeks was coconut oil 🤷🏻‍♀️ I don’t know why but it started to go away with just two days of using it. So I guess this stuff is better than any prescription cream we got.