When I was in Mooshu and my mission was to burn 3 outpost but when I tried to burn one it was already burned so I went to the other ones and they worked fine but I was not finished because they said I still had to get the last one. I logged out and back in and it was still burning plz do something about this. :D Thank you. :D
I had the same problem where towers were already burned.
What I did was just kept switching realms until I could find a tower not burned, and if I found one that I didn't burn, I would just switch realms again until I found an unburned one. So I would say just keep switching realms until you complete that task, like after every tower you burn.