Cash crate...........help!?

A few days ago i sighed up for cash crate, but now they are advertising their offers and surveys all over my computer. for example: if i am not on the website and i am on something completely different it still says things about game pickle of whatever it's called. and every time i get on to the browser a survey pops up. can you tell me why this is happening? and also if there is a way to stop[ it? THANK YOU!