You cannot currently upgrade either Legendary past applying the 2 Buillon item.
You have a ton of players that are waiting for this to get fixed so we can upgrade and continue on.
It was reported bugged on PTR. Bug persisted to live servers.
Can this please get fixed soon, rather than later?
Thank you
I donât understand, how does anyone have 4 buillons already?
Sorry, Iâm still working on the quests for the axe, so I havenât spent my 2 buillons yet.
The upgrade token is only 2 bullions.
Yay Blizz, yet again you took an extra hour on reset day and failed to fix a known issue.
I thought it can upgraded twice, requiring 4 buillons.
Nope just 1 time.
Ah, got it, thank you.
np 
It is all good.
wowhead posted about this, hopefully it will be fixed soon:
Thereâs also a huge thread on it in the bug forum:
absolutely but 3 hours now and not even a hint at "hey/we know/weâre working on it/we hear you/nothing.
radio silence as usual.
I have a feeling this is working as intended and the upgrades will drop off the boss when they are âkilledâ again. Like Mythic Sark and boom all the Dragon and next wee Mythic Frâyakk and Ding all the Axes can now upgraded.
Or you yourself need to get the kill to get to upgrade it, but something seems quite sus here indeed.
as i said on another post, bet you can only upgrade with scales LOL
Iâm sure theyâll fix it any moment now
Other threads talking about it being deleted isnât suspicious or anything
and that would be stupid since 1) The scale specifically says "Awaken the power within, increasing its item level to 502 and allowing it to be upgraded further. 2) That would literally screw EVERY. SINGLE. Ret, Arms/Fury/DK and Evoker that has a legendary basically forcing them to for-go every single awakening item on the vendors for the next 20 weeks.
Its interesting that they reduced the cost of flightstones for and i quote " * Reduced the Flightstone costs for Awakened and Special Awakened track Bullion items by 50%."
If special awakened track isnt the legendaries, then I have no idea. But they nerfed that but didnt fix the upgrades not being able to be done at all.
New BLUE:
Good luck with that⌠they knew it was bugged on PTR like you said, but itâs apparently not a quick fix.
Almost gonna be 24 hours to fix some weapon upgrade!! LOVE IT.
They had all that time in the extended maintenance to fix it, and they didnât bother with it. 
Ready to upgrade the Lego to 14/14 when servers launched. Spent the bullion and the upgrade vendor is broken. So not only do I not get the max Lego week 2 I have capped Flightstones. Have done 9 dungeons so far at cap waiting for this to be fixed. If their fix âtakes some timeâ, like 2 weeks then I could have gotten another item with my bullion. Played this game since launch and have had many disappointments but this might be one of the lamest. Reported on PTR and not fixed. Really sad that they could not have gotten out front of this and let us know it was going to remain broken in live. That that didnât happen is just terrible customer service and a complete lack of transparency.
Iâve saved all my aspects and flight stones just to upgrade my wep and I couldnât and still canât. This is making people have to use their resources on things they didnât intend because if the crest and flight stone cap. Now when they âfixâ it we wonât have any aspect to upgrade with. Microsoft and blizzard being stupid again
Same, I got capped and was all ready to max out my weapon and smash some keys with the boys
Now I sit here on a throne of flight stones and crests and they all giggle with glee with their new shiny maxed out weapons as I glance disheartened before my throne
There lays my weapon, unupgraded, unloved, and unhappy