I've noticed a bug that causes a party to become "locked": the party will no longer appear on the party finder and when people attempted to join from the mission interface, they are told that is no available party. Here is what I mean:

I start a party for the daily danger mission. After a minute or so a second player joins. The two of us wait 5-10 minutes and no one else joins us. I click on the missions tab, and select "join a party" for the danger mission and it allows me to join a new party. I asked the party leader if they created a party or tried to join a party and they said that they tried to join a party but got the "no parties available" message and so created one.

My party, for the same mission, was open and free to anyone to join. I never locked it, no one was kicked or went solo. So why did the client tell this new person that there were no parties available? I have seen this happen several times; I've asked the party leader if they tried to join a party and they have gotten the "no parties available" message even though I was in an open party for the same mission. It seems after 5-10 minutes, the party somehow hiddenly 'locks' and no one new can join from the mission interface.

It is rather annoying to have to repeatedly join new parties just to get a full one.