Facebook mobile troubles!?

Alright, so kay. i have 2 face book accounts one where its just family and the other is for my friends and such. my facebook mobile always goes to the sign in page it always has my family account email in. i will erase the email type the other one in correctly do the password correctly and it says i did incorrect log in and retypes my family account email!!! im so frustrated please help me figure this out. i use face book on my rumor touch by lg from sprint....please help