Missing Companion
So, I have more or less just finished Taris as my BH and as such unlocked Torian Cadera as a companion. I even summoned him, did a few short missions and added an item or two to his inventory. He appeared on my ship, I started the next missions, and then he's gone. Not on the ship, in none of my companion menus, nothing. I tried to log out and log back in, nothing happened. I did a bit more of the main story. No change. He still shows up in cutscenes, but in-game, he is nowhere to be found. I then tried to file a ticket with customer support, but the whole menu is greyed out. I can't even file a ticket.
They are doing some companion fixes in tomorrow's patch, it will reset the server so I would wait till after that patch to see if the issue is resolved. In the meantime you can try a few fixes:
Delete the DiskCacheArena file from the swtor diretory.
Log back into your game and try again.
If it's still not resolved try running a repair:
Non-Streaming launcher - Log into the launcher but don't click Play. Check for small letters "ST" in the bottom left corner. If this is NOT present, click the cog icon and then run the repair option.
Streaming launcher - If the letters "ST" is present, close the launcher, right mouse click on the game shortcut, select open file location and delete the BitRaider folder. Then start the launcher.