ph minus granules turned into liquid?

hey something weird happened to me. i have no idea how this happened but ive measured out ph minus for my pool but after doing another test i actually didnt need to lower the ph so i just left the granules in a small bowl for like 14 days and now i came back to it and a lot of it turned into liquid. as far as i know no one in my family added water to it and theres no way water somehow got to it since i left it inside. is there a scientific reason on this or did someone just add water to it without me knowing? im not very knowledgable in chemistry and i cant seem to find an answer online. appreciate your input.