Is anyone else having problems with Achievements not being unlocked in single player mode? I played the entire second Act without getting the Achievements.

Did you do it all on the same difficulty?

I also completed the second act (on the highest difficulty) without unlocking an achievement. Is this a glitch that can be solved without me doing the whole thing again??

im lost for words iv got all achievements apart from 1 single player master it will not unlock for the life of it any help would be great