I have 2 accounts on fb . both the accounts have same mobile no for login , bt only my second account opens .?

[rohit]

I created my Facebook account using my mobile no ( not email id ) . so whenever I used to login I've to enter mobile no and password. but the prblm is that I have another fb account which was also created using another mobile no . the second account which was created I wanted to change its no . so I went to setting and changed the no ( the no which was already registered to my first ac ).so both the account has the same mobile no . but whenever now I have to open my first ac I enter my password and mobile no bt it never opens ( my second ac opens ) . I can't open my first ac . I even tried to change the no from the second ac bt it fails .