Can't get or send invites

Earlier today I tried to summon a boss at a crowded spot and it didn't let me, the animation played and when the bar got full it didn't spawn.
Tried it a few more times and it said that the boss was already summoned, yet no quest for it in my questlog.

Now I want to party up with friends of mine and it says "You cannot organize a party while summoning a boss." while i've been in Calpheon for about an hour.

 

It sounds like your character is bugged, you will have to wait until the next server restart to get it fixed.