“Error 3009: Cannot Install Application’ encountered

My Blackberry Enterprise Service's version is 10.2.0 on my iPhone with iOS 7.1.1. I tried to open an app from work, but it failed. I could not download the app, it always gave me an error 'Error 3009: cannot install application'. 'Optional' has been always blank and there are no apps displayed on it. Any help please?
