help !! P8 pins Won't work

i just got an new beagle bone Black board for like a month ago and all was working well till i tried to use pins from P8 and discovered they are not working either as input or outputs ? what should i do or check ? please keep in mind that i am a beginner and i use the Cloud 9 to write my code and i don’t even know what software my board is working on (Debian or angstrom)