Lost my boss coins for the second time now

[albinRMADRID]

Can you please explain why I lost 40 coins 2 weeks ago when i tried to buy one player, and now today it happened again when i try to buy one player from transfer list and I didn't have enough money but i wanted to buy with coins, it just took my coins I still couldn't get the player just lost the coins. please explain because this is being repeated and is making me uninstall the game