@Audrey I'm honestly not sure material what they are they're mostly Charlie banana and bum genius in on city water it isn't really hard but did leave some spots should I be adding borax or vinegar to soften it in the wash? How would I know if it's yeast?
I'm not as familiar with CB, but I think BG are all cotton. Microfiber (aka "charcoal bamboo") tends to be problematic. There are some tests you can do to see if you have hard water, but I ended up just buying a digital tester from Amazon. I wouldn't add borax without checking first, and personally I'm not a fan of putting vinegar in the machine. I know a lot of people do, but I think it can cause issues and void warranties. Dryer sheets and fabric softener can cause buildup that leaves a residue and keep them from getting clean. I don't remember the specific signs of yeast, I'd have to Google it. I remember battling it with my youngest, but he's 4 now. We were about to potty-train so ended up just using disposables those last few months.
What type of diapers are you using (material - cotton, microfiber, hemp)? Have you checked to see if you have hard water? How are you drying? No fabric softener or dryer sheets, right? If you suspect yeast, you'll need to bleach soak *everything* and either stop cloth for a couple of weeks or bleach them every time.