Guild Wars 2

So I’ve recently noticed that often when I stack might it won’t show up above my bar with my other boons. Has this happened to anyone else?

The “Area Might” tick shows up when the combo goes off but I don’t receive the stacks. Any light on this subject would be appreciated.

Thanks!

You are too far from the fire field that is being blasted.
Blast finishers apply their effect to all foes or allies in the area where the blast occurred with radius 360.
http://wiki.guildwars2.com/wiki/Combo