Asitis — Creatinine monohydrate is not mixing in water

I have ordered asitis brand creatinine monohydrate, after opening it it is not mixing into the water. when i wrote email to the company they asked for the vedio of the product that it is not mixing. After providing vedio they are telling to use it with some euipped bottle. But the product is water soluble it should dissolve without using euipped bottle as other product creatinine rapidly dissolve.