you need some yeast ENERGIZER in there. nutrient is good, but energizer is full of the nitrogen yeast needs to thrive, and that honey lacks. Beer wort is full of nitrogen and thus doesn't need the energizer.
7 weeks is just too long for mead. you should hit attenuation on a recipe like yours in 4 weeks or less.
I would indeed pitch another sachet of yeast. I wouldn't make a starter, you can rehydrate though, and I'd put the energizer in the hydration water just to help mix it.
I've also had success adding fruit to a stuck fermentation, as the nutrients and nitrogen will help the yeast resume fermentation. unfortunately you'll lose some of your orange blossom honey flavors as the fruit will over power it.
Primary: English Mild
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