We have a Hotpoint Aquatis AQGD 169 S washing machine, and the plastic drum paddles inside the drum keep breaking off, we have had the machine about 18 months and no problems but i have changed 2 paddles in about 6 weeks. Is there a special way to fit them because there is a bit of metal in the middle that is stuck up every time it breaks,but you can't fit a new paddle unless you flatten this piece of metal. Is the piece of metal supposed to be up or down and any explanations why paddles are breaking?