If your dehumidifier is not functioning correctly and the compressor appears to be functioning it is possible that the humidity setting has not been set low enough for the room in which it is operating. As a result the dehumidifier is not able to run long enough to adequately remove additional moisture from the air. Please lower the desired humidity level setting and see if your problem is resolved.
If lowering the humidity setting does not resolve your issue then there may be a problem with the humidity sensor (humidistat) or the compressor component.