i found this while trying to resolve my problem this guy explains it better then i do
Issue with Game Center and Clash of Clans
Long winded I realize....
I have clash of clans loaded on my phone and have gotten to level 30 something so I have some time invested. My wife purchased a new IPAD and I wanted to load my COC on bigger screen. So I followed the directions of logging her out of game center -> logging myself in (yes using my same ID and PW) -> and attempted to load my COC game on her IPAD.
Unfortunatly when I brought the game up it was a new game (level village and the game said welcome *My Wifes id* so I close it out and logged myself out fearing the worst.
Well i have not lost everything but here is what I have now......... Each time I chose the game on my Iphone it asks.......
GAME CENTER ALERT
Do you want to load Chief *insert name here* village with Town Hall 1
Warning current game progress will be lost.
How do I resolve this? PLEASE HELP