Hidden Steam Achievement bugged *SPOILER*

I have had a 4x multiplyer for a combined time of at least an hour an twenty minutes and the game is not giving me the achivement.

i used a stop watch to measure how long ive been going for this achievement because i noticed ive been playing too long prior to not be given the achievement.

You need a COMBINED TIME of an hour not an hour straight I have certainly have had the required multiplyer for at least an hour.

I could be wrong but there is no way to check in stats in game.