First of all, thank you very much for explaining the situation. But now I'm a bit dissatisfied :) Not only do I now own the club, but I also received the entire FG. As mentioned in the topic, I just wanted to know if the transaction was a bug or an unlucky trade. So that I can complete this here, I'm sending the returned FG back and keeping the club in return. Since my friends and I now understand the transaction, I can write this off as the "rarest of unlucky trades."
I can only agree ;)
I previously stated that it is a rare (extremely) incident of timing... just unlucky... however it is kinda lucky, because the community now knows it can happen. How to fix this is game mechanics.
Do as you please with the information given by others and what I assessed myself.