I recently made a batch of a La Trappe Quadruple clone and used a vial of Trappist Ale high gravity yeast. I transferred to the secondary and basically the fermentation didn't stop (it slowed down but stopped) so I siphoned it off the yeast cake and put it in another per fermenter (3rd?). After priming with light DME as directed in the recipe the beer is totally flat. I tried one bottle with some table sugar in the bottle and waited a week, still flat. I also tried the carbonating tablets and they did nothing either. Can anyone tell me what my problem is other than flat beer. Thanks!