Broken fan, most likely. They usually won't tolerate something much heavier than a penny, especially when they're weak from being worn. Best to let a vac. repair place do that. I usually don't charge alot to replace them. If the place is reasonable, it will be cost feasible to have it done.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix vacuum cleaners.