Umm idk about ur baby but mine is a girl and started exploring her genitals. I got abit worried too because its pretty early to explain and i also thought she was feeling itchy but honestly might be exploring body parts. Probably need to talk to a paediatrician about this and figure out what can be done.
mine is a boy too and he does the same at 15 months. i don't think its the soap that is itchy. he is probably sort of exploring but not to that extent so don't have to worry so much about it 😄