I was playing the game by myself and was in Uldah, I wanted to teleport my buddy playing the game right beside me to Gridania, I sent him the party invite, I thought he had accepted so I teleported, he actually accepted right as I teleported (when my screen went black), once Gridania loaded I was not shown to be in a party and neither was he. When ported back to Uldah and tried to add him to my party again it said he was already in a party, and same thing when he tried to add me, but neither of our screens showed we were in a party. I logged off then back on, and then was able to add him to my party and port to Gridania.