I can only click on it once / login, and I get disconnected after. Also the same uncrafted lvl 1 merc occupies both slots and “preparing” progress bar never moves. All my mercs are level 30 anyway, but I still want to open more.
Issue since release. I was unable to use it or make any progress. Even buying it was bugged; Several disconnects, paying never finished processing, and my remaining gold should be over 4000, not merely 3000…
5 hours ago
Daniel
DxDiag.txt
MSInfo.txt
3 hours ago
Cruyvvers
Greetings Daniel,
and thank you for taking the time to contact us and for reporting this issue.
Sadly Customer Support as for today only provide basic Tech and Billing support when it comes down to Hearthstone and I am sorry to say that we will not be able to help you with this occurrence 
If you have issues of this kind it is very likely that devs themselves need to be notified of the issue and find and solve the root cause of the problem.
Please be sure to post on our forums regarding any in game issue you may be encountering
I’m sorry that I could not assist you with your request this time, if you have any more questions or doubts please do not hesitate to contact us again and we will do our best to assist you.
Take care /wave
Luca, aka Game Master Cruyvvers,
Blizzard Customer Support