Can't create account on the World server on my ios device

[R01Ss999]

Hello, I have already submitted a ticket with this issue but no response so far so Im trying my luck here.
So a few years ago a friend of mine who plays osm since 2012 asked me to install osm on my iphone 7 Plus at the time so he could set up his team and I didnt play so I just let him do it. Last year my friends finally convinced me to start playing the game too so I tried to create an account of my own but every time I loaded up OSM it would automatically enter his account. I did some research and changed server to "Dutch". That worked and I could create my account BUT I what I didnt know was that I wasnt able to play with them or add them as friends even. I kept playing on this account because I couldnt find a way to play on the "World" server without it entering my friends account. This week I bought a new iPhone and I thought I could be able to FINALLY create an account and play with them. But I was wrong, IT STILL loads his account and I can't create a new one of my own. Everything I just said will surely be backed up by logs or the data the app collects, I would just like to disconnect his account from my device so I could play on the "world" server with them. Thanks in advance!

[SpecialOne]

When your friend logged on your device, he also linked it to your gamecenter account, that's why it keeps logging on his account.

You can fix this yourself by removing the link (you can do it on OSM settings)

NOTE: Let your friend know that he needs to secure his account by setting an e-mail, so he can recover it if he switches device/forget pass.... etc