hard to say without knowing more. just some basic things to check-

edit: comp gifts are not part of the high lvl missions. link - bottom of page, crew skills -

http://www.swtor.com/patchnotes/2.0-rothc/rise-hutt-cartel-and-scum-and-villainy

are you at least lvl 50?

do you have the credits to buy the upgrade ( 10,000 I think )?

is your crafting and gathering skills at lvl 50 as well? ( don't know if that matters, though worth a look ).

did you actually get the upgrade and just didn't realize it? ( run a few missions and see if you get some points ).

the new underworld trading missions don't show up till you reach 410 I think. ( could be wrong about that one ).

run the client repair option from the launcher ( bottom left, little gears, launcher window ).

ctrl + U twice to reset the User Interface.

contact CS and or bug report ( in game might be best )

edit -

In addition to the above you need the Rise of the Hutt Cartel update, have you purchased this?

other than that I'm not sure off hand what else to try. best of luck -

In addition to the above you need the Rise of the Hutt Cartel update, have you purchased this?

excellent point, totally missed the most obvious question - - thx monty!

The other stuff mentioned is mostly irrelevant(although I do realize the poster was trying to be helpful. no offence intended!). You don't need to be level 50 to train any skill for advanced. You don't require a certain level in any associated or non-associated gathering skills. You could have a toon with only a single skill at 450, if you choose. I've got a level 13 bounty hunter that has 450/450/450 skills. The advanced crafting is part of the RotHC expansion, so it is a necessity to train above 400 in any skill. So all you need to train is 10,000 credits, and the expansion purchased. If you have both of these prerequisites, and still cannot train, I would file a ticket.

Additionally, does your skill after supposedly training say 400/400 or 400/450? I'm a bit unclear if you've actually purchased the training, yet don't have the new missions available, or are simply unable to get the training. I've found with crafting professions the new tier stuff starts around 410. Gathering professions may require 401. So if you have purchased the training, make some grade 6 stuff still to get some more points, and then check to see if the new tier of crafting opens up. From memory, I don't think they opened exactly on 400 for gathering skills. Send out a few more yellow difficulty mission, is my recommendation...

so i have 400/400 crew skill on underworld and when i go to the trainer and click on the underworld advenced upgrade nothing happens??, what do i need to do? i have grade 6 metal grade 6 fabric, and grade 5 companion gifts, do they all need to be grade 6??

Note that the level 49-50 missions are still green or yellow. You need to run at least one of them to get to skill 401, at which point the level 51-55 (skill 401-450) missions will show up.

The other stuff mentioned is mostly irrelevant(although I do realize the poster was trying to be helpful. no offence intended!). You don't need to be level 50 to train any skill for advanced. You don't require a certain level in any associated or non-associated gathering skills. You could have a toon with only a single skill at 450, if you choose. I've got a level 13 bounty hunter that has 450/450/450 skills. The advanced crafting is part of the RotHC expansion, so it is a necessity to train above 400 in any skill. So all you need to train is 10,000 credits, and the expansion purchased. If you have both of these prerequisites, and still cannot train, I would file a ticket.

 

Additionally, does your skill after supposedly training say 400/400 or 400/450? I'm a bit unclear if you've actually purchased the training, yet don't have the new missions available, or are simply unable to get the training. I've found with crafting professions the new tier stuff starts around 410. Gathering professions may require 401. So if you have purchased the training, make some grade 6 stuff still to get some more points, and then check to see if the new tier of crafting opens up. From memory, I don't think they opened exactly on 400 for gathering skills. Send out a few more yellow difficulty mission, is my recommendation...

no offense taken - - good info is better than poor ( irrelevant ) info any day and I learned a few things to boot.

thanks for the clarification!

In addition to the above you need the Rise of the Hutt Cartel update, have you purchased this?

QFT

There is no level requirement, however you need the extension to go over 400.