SWGOH: Lost account after iOS update / Game Center issue

Hi, I lost my account after I updated iOS. I played SWGOH on my iPad and never logged in into Apple Game Center. A couple of days ago I tried to play on my iPhone and on this device I was logged in into Game Center. After I installed SWGOH a new account was created and I was not able to log into my existing SWGOH account from within the app. So I uninstalled the game and figured that that in order to play on more than one iOS devices I would have to find a way to link my existing account to Game Center. Unfortunately after I updated iOS on my iPad I was logged into Game Center and SWGOH just linked the second account I created on my iPhone.

What can I do now. I have my Player ID, ally code, mail adress ... I invested a 4-digit amount of money and dont want to lose all of this.