I developed a red rash too and it itched like crazy. I went to see my doc, GP, about it and she said it was a fungus rash. She prescribed me an antibiotic cream to put on it and it got rid of it quickly. I pour soapy water into my bag when cleaning it and rinse with clear water. Then I roll up a paper towel and dry it out inside. Works for me to keep things clean. I hope your issues get better soon!