attack skills missing after equipping lock crate looted weapons

[Lug]

Hi,
I opened some locks on my 71 HC warrior character and looted some legendary 71 weapons.
The problem is that both my skyward smash and whirlwind attack skills become black circles and cannot be used (the other two skills of vengeful blood and horn of renew are not affected).
If i try using an epic level weapon, all the skills return but not when i equip any legendary weapons i have looted from the locks.
i have tried reinstalling the game, logging on multiple devices but it has not solved the issue.
i have attached a screen shot where you can see the darkened skills.
If you could help to resolve this, it would be really appreciated.
Cheers,
Lugling

[caabarader]

That means u don't have enough mana to use them, so probably ur new equipament has low mana compared to previous one

Enviado de meu SM-A037M usando o Tapatalk

[Futumsh]

This means your maximum mana is less than the cost of the ability. Put some points in intelligence, or adjust your gear to have more.