Complex sentence: Not only that but the team managed to do it twice in succession, and some lows, when FIFA/UEFA reacted strongly against Bosnian FA and banning the team for a short period in 2011.
Split into simpler sentences: Not only that but the team managed to do it twice in succession. And of course some lows, when FIFA/UEFA reacted strongly against Bosnian FA and banned the team for a short period in 2011.