Fermentation help needed

A friend and I attempted a barley wine, I made a start using WPL099, 2 cups H20 and 1/2 cup of DME. It was on the stir [plate for 36 hours or so. Aggressive activity took place and the krausen was ~9 inches. Fermentation stopped at the 7th day..the issue is, OG was 1.098, FG indicated 1.076, this is less than 3%??? There's plenty of sugar left over (tasted it)......Any Ideas???

I racked it anyway and added 1 pkg LALVIN EC-1118 into the secondary yesterday....very slight activity after 24 hours...

Thanks!

Its possible that you under pitched. 1.098 is a pretty high gravity and usually you need a couple liters of starter or multiple yeast packs. Check www.mrmalty.com/calc/calc.html and see how much yeast you need. Temperature could also affect the yeast if allowed to drop low enough but I doubt that was the issue.

Were you using a hydrometer to measure?

Morning...I don't believe I under pitched it...used a solid starter... see info below..

I did Use a hydrometer...

the recipe used:
120 minute boil
21 lb Wester 2-row
2 lb Crystal 30-37 L
1 lb Munich
3.5 oz Roast Barley

2 oz East Kent Goldings
3 oz Centenial

I mashed in at 155 for 60 minutes, conversion tested great..sparge temp 170 (about 6.5 gal of wort used). I thought my OG was a little light for a barleywine... I just did an IPA, OG was 1.1, and a double IPA, the OG was 1.14 (racked at 11.6 ABV), I've never had a problem with big beers till now. In comarisom to others I've made, wasn't that big??

I did the fermentation about 70 degrees, it fluctuates +/-1 degree....tried to spin method but didn't do anything, so I racked it, add the champagne yeast 48 hours ago, it's been outgassing 2 per second for the last 18 hours, keep your fingers crossed..LOL

I did taste it it's very very very sweet... I appreciate the replies.....

thanks