I cant log in but have Game Center data

I loved this game and use to play it all the time last year. I got my new phone and went to download and log in but the Game Center data didnt load. I opened my Game Center and the achievements Ive unlocked where still there. I really dont want to start over because Ive already put so much time into my previously existing characters. I would love if one thumb could troubleshoot my issue.

Burly_man about Celtic Heroes - Mobile MMORPG