Hi all! I'm new to iPhone 4s please help me guyz!

[Sarah_Helpmeplzzz]

I found my iPhone 4s contacts list and all of my stuff on my friend's iPhone 4s how did that happen!? I guess maybe it was because of that stupid ICloud i think i merged my contacts with it by accident how can i undo this or reverse it!? is there any way i can fix this?
note that me and my friend are using the Same Apple ID! thank u.

 

[ericsinsideout]

my first thought is that you should both probably get separate Apple ID's

 

[MoneyMaker79]

Separate Apple ID's is the first thing. Also, syncing two iPhone's to the same iTunes could have caused contacts to be on your friends iPhone. That happened with my mom and I. Her iPhone was restored on my iTunes awhile back, and now I restored and had her contacts. Very strange. To fix your friends iPhone contact list, do they have an old backup or recent that they can use?