Why can I not receive anymore than 800mb's TOTAL available space for my apps.??

[AC Question]

I have a Ellpses 7 Tablet. My wife bought it from a woman at her old job in NJ, It says 3.5 G's available, But it won't give me anymore than 800 MB's for my "TOTAL" AVAILABLE APP. SPACE!!?? I HAVE WENT INTO THE FACTORY SETTINGS AND REBOOTED IT A MASTER FACTORY RESET ETC. NOTHING HELPS!!??? PLEASE SOME ONE OUT THERE PLEASE HELP ME FIX THIA PROBLEM. IS IT A ROOT PROBLEM' SOME HOW DID THE PREVIOUS OWNER PUT SOME KIND OF LOCK IN IT?? PLEASE CAN I GET SOME HELP??

Thank You,

Sincerely,
Mark M.