Really need to know the name of the faucet. But it sounds like there is rubber or plastic in the stems, and they have become swollen and or waterlogged. Your water may be to hot. And if it is not A name brand faucet, I would not waste my time trying to find parts. If it is like A Glacier Bay, or something similiar forget about it.But it could be Moen, Delta, Kohler, American Standard. And please don.t say Price Pfister, they are OK until they go bad, then the hunt is on for parts.
If you are not part of the solution, then you are part of the problem.