What's the temperature?
Also, can you verify the pH and the gravity again?
To get it done you may have to build it up from a starter, but in this case. You'll need a heavy-duty yeast like EC-1118 (premier cuvee), DV-10, or Uvaferm 43. To do this you rehydrate a couple of packets of yeast, and make a small starter (you can use a little malt extract if you like) and put this in another fermentation bucket or carboy. Then start doubling the volume by adding amounts of your must, waiting for the bubbling to pick up before each new addition. You keep doubling the volume until you have all the must in the new fermenter. It is a bit of work, but it rarely fails.
If, for some reason, it still isn't moving, there are still some other steps you can take including pasteurizing the whole batch. You can also start an entirely new large batch and when it is going strong, you can mix in your old batch a portion at a time until it is all finished. So though this may be a bit frustrating, Endeavor to Persevere.
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