I am The guild leader of Outlaws_Inc. I and my vice leader we're trying to attack each other's bases, I was able to attack his but you was not able to attack mine. It said you can't attack another player while they are online, but I closed the application and had my phone screen turned off. I am the only person who has access to my account oh, I did not have a shield. I am not sure why it did this, but a fix to it would be greatly appreciated. As always IGG you are best, please look into this.
Situation like this happens, under certain circumstances, but there is nothing we can do about it, as it was wrote here many times. In newest update you will be able to "Practice with Friends". Let's hope this will be same thing.