Alright... so not my best moment, but here's what happened. I acquired my 1st legendary weapon and got the quest (Vol 2, Book 1, Ch11) where I need to advance my item by killing monsters, etc. Well, during the Anniversary Festival I acquired a Heritage Rune and applied it to my weapon to 'save some time', but it didn't count towards my quest and I need to reforge it. But I can't use the Forge Master, so I'm a bit stuck. I tried unequipping it and reequipping it, then killing a monster of my level, but nothing happened towards my quest completion. Help?
Sounds like you should get in touch with a GM and maybe talk to them about the possibility of resetting that quest for you and deleting the weapon you have now. You would have to start that series over again, but at least you could get it done right and be able to use the forge/relic masters. Might be another way to solve it, but thats the first thing that comes to my mind.
First you need to bug it. Now that runes are account bound it is going to be a much more common problem. If you use a rune on your fist LI you cannot reforge it.
Then you need to submit a ticket and hope they fix it for you.
Definitely try the forgemaster at Thorin's Hall or Rivendell. Back when Moria was released, those were the only ones you could access before you could enter Moria.
Unless they changed it, the quest specifically directs you to those forgemasters, though I can totally understand why you'd try the one at Echad Mirobel or something.