Back to basics! Wine is what happens after the sugar in grapes is converted to alcohol with the help of yeast, through the process of fermentation. The extra, hungry yeasts without any sugar to consume will end up dying and settling to the bottom along with the rest of the lees and sediment.
Yeasts need oxygen in order to permit sufficient growth of new cells, which are what are going to do the work of fermentation. If fermentation hasn't started at all, then try aerating or oxygenating it again, and preferably re-pitch with a fresh batch of yeast.