There are those who swear by the Wyeast Sweet Mead yeast strain, and those who swear at it. I'm in the latter category. I have never had consistent results with that yeast and I have more often than not had fermentations stall well short of my planned FG, so I have for all practical purposes abandoned it.
That said, you can try a couple of things before resulting to pitching a new yeast to try to coax a re-start. First, bring your fermenter into a warmer spot. If your basement is on the cool side, that could cause your yeast to poop out early. And gently swirl the flocculated yeast back up into suspension to encourage any still active yeast cells to begin fermenting again. If a week at a warmer temp doesn't get things moving, then the next thing I'd do is to check the pH of the must. It sounds from your description that this is a traditional mead (just honey and water) so it may be that the must became too low in pH to sustain healthy yeast cells. You can adjust pH with a little potassium carbonate or potassium bicarbonate, if needed.
If neither of those things work, you can re-inoculate with an acclimated yeast starter. I would recommend that you choose a yeast strain known to be good at re-starting stuck fermentations, and to follow the guidelines for acclimating your yeast that you can find here on the forum if you search for stuck fermentation.
Finally, you may want to use a different yeast strain in your batches going forward.
