Invaders not Invading

[Grinning Grenadier]

Has anyone experienced this? It seems to only happen in East Osgiliath but an invasion is called and the invasion armies show up and just start loitering around the city and never attack. This has been going on now for many turns forcing me to attack these armies instead of smashing them against my city walls. Some of the armies have even taken to wandering down to Southern Gondor but don't actually do anything.

[Muffer Nl]

Just wait they will move on evtually. They are probably blocking each others path.