How To Update V12 to V13.5.6?

[OddOracle1832]

Hi! Couple years ago I played the game in V12 version, and I can't manage to update it to 13.5.6. The posts say I need to save the game in League Administration but I don't remember where is this building, and even at which point I was in the V12 save file. I would continue the game in that version but I just don't know where to go or what's the next step. I have 14 badges currently.

 

Thanks!!