Bests & Worsts Reviews from Amazon

I have been ordering the item for months but suddenly i got a batch w/ a nasty looking film on the cap. I tried shaking it before giving to my kids but it won’t get off. It does not smell bad, but at the same time, when i tasted it, it is like a gritty chocolate. Very nasty. I am not sure if this is an amazon issue or a manufacturer issue. But i am disappointed.