Help! Hamster's water bottle isn't working properly.. =(

My wife and I just got a hamster but his water bottle doesn't seem to work! when we fill it up, touching the ball on the end gives water like it should, but after an hour or two it's totally dry unless you push the ball 15-20 times. Is this normal?

We have 2 different water bottles and it's like this on both of them, is there a special way to fill them we aren't aware of? Thanks