Hello,
I am unable to disenchant cards manually. By this I mean that when I view a specific card and it gives me the “craft” and “disenchant” options, pressing “disenchant” does nothing. I can craft and mass disenchant.
This bug is stopping me from disenchant cards I no longer need, and is currently stopping me from getting the full dust refund on Jandice Barov. I have tried to disenchant a variety of cards, with none working.
Hopefully this can be resolved.
Having the same issue, did they ever help you with a fix?
Same issue here for the past month. I tell you if I have news from Blizzard.
I found a fix, what worked for me was: Clearing out all my achievements, I had a duel that i had not completed, i retired from that . Seems like once everything was cleared, i was able to disenchant again.
I still have no fix. My Duels is also still currently broken, as has been for months, as it is stuck at the end of my run. 
Incredibly frustrating being unable to disenchant unwanted and golden cards.