I've thought the same thing, h pylori came up when i was searching both NAC and mastic.
I had a metametrix stool test done and H pylori came up positive, after that I took Antibiotics but there was no relief from my state of illness. I had a blood test done to assess if I still had h pylori after the Antibiotics which came back negative so I don't know what's going on.
perhaps there is some ongoing gut damage that permits microorganisms to grow, I've done an Elimination Diet but haven't found any relief, tried pancreatic enzymes and ox bile but my stools are still perpetually a light shade of brown and covered in undigested bits of food. I'm trying HCL again right now but so far nothing's come of it.